. there is the old adage that you get what you pay for . . . why buy a poorly designed antenna that does not work very well
?
If you have a 5 element yagi that only produces 4 dbi you are not getting what you paid for . . . most 2 element yagis would out perform that statistic . . . a 5 element yagi should be at least 9 db + or 10 db dbd (dipole ) not isotropic . . . . there is something that is called MERCHANTABILITY . . .i.e., an IMPLIED WARRANTY that you are getting at least the minimum for your money . . . 4 dbi for an Arrow is way off base . . . so it is not just ; you can not afford a Cadillac but you are not even getting a Ford or Chevy . . i.e., the gain of a 5 element yagi on 435 mhz . . . that is the issue, not cost alone . . . . . . same comments apply to the ELK but I have attempted to make the point that there is a minimum performance for a certain number of elements that is pretty OBJECTIVE and when it is not met . . . . well that is my point . . . these two antennas have shown to some testers that they do not measure up to the minimum EXPECTATIONS . . .unfortunately that is acceptable to some . . . . then it becomes acceptable to many . . . and objectivity is abandoned . . .
Jim W9VNE
----- Original Message ----- From: "Trey Brown" [email protected] To: "Jim Danehy" [email protected] Sent: Saturday, December 27, 2008 6:39 PM Subject: Re: [amsat-bb] ELK or ARROW
Thanks for the comments. Realize, though, that not everyone wants or can afford to have the Cadillac.
On Sat, Dec 27, 2008 at 4:06 PM, Jim Danehy [email protected] wrote:
the Arrow antenna has been critiqued by Kent Britain, WA5VJB
http://wa5vjb.com/references/Cheap%20Antennas-LEOs.pdf
he says that some have measured the Arrow for gain on 435 mhz @ 4 dbi (isotropic) . . . . and that further analysis showed that for the element lengths used on 435 mhz that it peaks at 457 mhz and not 435 mhz . . . Kent is a well respected VHF/UHF antenna person who has plenty of credibility . . .
Kent opines that the Arrow, as built does not have its elements insulated from the boom. It uses dimensions for insulated elements . . . so much for the Arrow . . . .
Now for the ELK : a local friend of mine owns an Arrow and he uses it successfully. He bought an ELK and attempted to compare the Arrow and the ELK . . . . he could not make an across town QSO on 435 mhz from his second story window with the ELK , so he sent the ELK back for a refund .
I have worked and exchanged QSLs with several hundred satellite users . . .the majority of the folks that have worked and QSLed me (close to 250
- ) have been using either the Arrow or ELK based upon the information
on their cards. So they are popular. Are they optimum ? A lot of anecdotal information would seem to say NO . . .
Thirty-five years ago I worked Oscar 6 with a homebrew 2 mtr yagi that probably was worse than either the Arrow or Elk but I worked YV and KL7 from Indiana on CW with about 15 watts to the 3 elements which my XYL waved around at my directions . . . not any more . . .what do I use these days : a pair of circular polarity yagis on 10 foot booms manufactured by M Square . . . .
Folks ask what should they buy ? Maybe a Ford or maybe a Chevy . . . neither is a Cadillac . . . .
Jim W9VNE _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
-- Trey -- N5THX
They who can give up essential liberty to obtain a little temporary safety, deserve neither liberty nor safety.
- Benjamin Franklin
To All, 1. Amateur Radio is learning by doing. 2. A large amount of data on Yagi type antennas exists, easily found, and is well proven. 3. Several design programs for antennas exist reducing construction time and waist of materials. 4. Equipment to measure comparative antenna performance at VHF/UHF frequencies is not hard to find.
Why do we line the pockets of some poorly designed antenna manufacturing companies instead of learning how and making the best performing antennas for our own use? If we do not learn these skills, no one will be left to teach and the skills will be lost.
There are many older Amateurs willing to teach those that want to learn, and hopefully many of those wanting to learn are at least one half of the age of those who can teach!
Art, KC6UQH
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Jim Danehy Sent: Saturday, December 27, 2008 6:33 PM To: [email protected] Subject: [amsat-bb] Fw: ELK or ARROW
. there is the old adage that you get what you pay for . . . why buy a poorly designed antenna that does not work very well
?
If you have a 5 element yagi that only produces 4 dbi you are not getting
what you paid for . . . most 2 element yagis would out perform that statistic . . . a 5 element yagi should be at least 9 db + or 10 db dbd (dipole ) not isotropic . . . . there is something that is called MERCHANTABILITY . . .i.e., an IMPLIED WARRANTY that you are getting at least the minimum for your money . . . 4 dbi for an Arrow is way off base . . . so it is not just ; you can not afford a Cadillac but you are not even getting a Ford or Chevy . . i.e.,
the gain of a 5 element yagi on 435 mhz . . . that is the issue, not cost
alone . . . . . . same comments apply to the ELK but I have attempted to make the point that there is a minimum performance for a certain number of
elements that is pretty OBJECTIVE and when it is not met . . . . well that is my point . . . these two antennas have shown to some testers that they do not measure up to the minimum EXPECTATIONS . . .unfortunately that
is acceptable to some . . . . then it becomes acceptable to many . . . and objectivity is abandoned . . .
Jim W9VNE
----- Original Message ----- From: "Trey Brown" [email protected] To: "Jim Danehy" [email protected] Sent: Saturday, December 27, 2008 6:39 PM Subject: Re: [amsat-bb] ELK or ARROW
Thanks for the comments. Realize, though, that not everyone wants or can afford to have the Cadillac.
On Sat, Dec 27, 2008 at 4:06 PM, Jim Danehy [email protected] wrote:
the Arrow antenna has been critiqued by Kent Britain, WA5VJB
http://wa5vjb.com/references/Cheap%20Antennas-LEOs.pdf
he says that some have measured the Arrow for gain on 435 mhz @ 4 dbi (isotropic) . . . . and that further analysis showed that for the element lengths used on 435 mhz that it peaks at 457 mhz and not 435 mhz
. . . Kent is a well respected VHF/UHF antenna person who has plenty of credibility . . .
Kent opines that the Arrow, as built does not have its elements insulated from the boom. It uses dimensions for insulated elements . . .
so much for the Arrow . . . .
Now for the ELK : a local friend of mine owns an Arrow and he uses it successfully. He bought an ELK and attempted to compare the Arrow and the ELK . . . . he could not make an across town QSO on 435 mhz from his
second story window with the ELK , so he sent the ELK back for a refund .
I have worked and exchanged QSLs with several hundred satellite users . . .the majority of the folks that have worked and QSLed me (close to 250
- ) have been using either the Arrow or ELK based upon the information
on their cards. So they are popular. Are they optimum ? A lot of anecdotal information would seem to say NO . . .
Thirty-five years ago I worked Oscar 6 with a homebrew 2 mtr yagi that probably was worse than either the Arrow or Elk but I worked YV and KL7 from Indiana on CW with about 15 watts to the 3 elements which my XYL waved around at my directions . . . not any more . . .what do I use these days : a pair of circular polarity yagis on 10 foot booms manufactured by M Square . . . .
Folks ask what should they buy ? Maybe a Ford or maybe a Chevy . . . neither is a Cadillac . . . .
Jim W9VNE _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
-- Trey -- N5THX
They who can give up essential liberty to obtain a little temporary safety, deserve neither liberty nor safety.
- Benjamin Franklin
_______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
__________ Information from ESET NOD32 Antivirus, version of virus signature database 3719 (20081227) __________
The message was checked by ESET NOD32 Antivirus.
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Art
Well said . . . . I love fooling around with antennas of all sorts . . . hard for some to build rigs but antennas much easier projects . . . a ton of engineering info out there as you say . . . ARROW and ELK work but can work better with some tweaking . . . have fun . . . there is DBi (isotropic) and DBd (dipole) but do not forget DBa (advertising) the latter is more abused than the other two . .
Jim W9VNE
----- Original Message ----- From: "Art McBride" [email protected] To: "'Jim Danehy'" [email protected]; [email protected] Sent: Saturday, December 27, 2008 9:59 PM Subject: RE: [amsat-bb] Fw: ELK or ARROW
To All,
- Amateur Radio is learning by doing.
- A large amount of data on Yagi type antennas exists, easily found, and
is well proven. 3. Several design programs for antennas exist reducing construction time and waist of materials. 4. Equipment to measure comparative antenna performance at VHF/UHF frequencies is not hard to find.
Why do we line the pockets of some poorly designed antenna manufacturing companies instead of learning how and making the best performing antennas for our own use? If we do not learn these skills, no one will be left to teach and the skills will be lost.
There are many older Amateurs willing to teach those that want to learn, and hopefully many of those wanting to learn are at least one half of the age of those who can teach!
Art, KC6UQH
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Jim Danehy Sent: Saturday, December 27, 2008 6:33 PM To: [email protected] Subject: [amsat-bb] Fw: ELK or ARROW
. there is the old adage that you get what you pay for . . . why buy a poorly designed antenna that does not work very well
?
If you have a 5 element yagi that only produces 4 dbi you are not getting
what you paid for . . . most 2 element yagis would out perform that statistic . . . a 5 element yagi should be at least 9 db + or 10 db dbd (dipole ) not isotropic . . . . there is something that is called MERCHANTABILITY . . .i.e., an IMPLIED WARRANTY that you are getting at least the minimum for your money . . . 4 dbi for an Arrow is way off base . . . so it is not just ; you can not afford a Cadillac but you are not even getting a Ford or Chevy . . i.e.,
the gain of a 5 element yagi on 435 mhz . . . that is the issue, not cost
alone . . . . . . same comments apply to the ELK but I have attempted to make the point that there is a minimum performance for a certain number of
elements that is pretty OBJECTIVE and when it is not met . . . . well that is my point . . . these two antennas have shown to some testers that they do not measure up to the minimum EXPECTATIONS . . .unfortunately that
is acceptable to some . . . . then it becomes acceptable to many . . . and objectivity is abandoned . . .
Jim W9VNE
----- Original Message ----- From: "Trey Brown" [email protected] To: "Jim Danehy" [email protected] Sent: Saturday, December 27, 2008 6:39 PM Subject: Re: [amsat-bb] ELK or ARROW
Thanks for the comments. Realize, though, that not everyone wants or can afford to have the Cadillac.
On Sat, Dec 27, 2008 at 4:06 PM, Jim Danehy [email protected] wrote:
the Arrow antenna has been critiqued by Kent Britain, WA5VJB
http://wa5vjb.com/references/Cheap%20Antennas-LEOs.pdf
he says that some have measured the Arrow for gain on 435 mhz @ 4 dbi (isotropic) . . . . and that further analysis showed that for the element lengths used on 435 mhz that it peaks at 457 mhz and not 435 mhz
. . . Kent is a well respected VHF/UHF antenna person who has plenty of credibility . . .
Kent opines that the Arrow, as built does not have its elements insulated from the boom. It uses dimensions for insulated elements . . .
so much for the Arrow . . . .
Now for the ELK : a local friend of mine owns an Arrow and he uses it successfully. He bought an ELK and attempted to compare the Arrow and the ELK . . . . he could not make an across town QSO on 435 mhz from his
second story window with the ELK , so he sent the ELK back for a refund .
I have worked and exchanged QSLs with several hundred satellite users . . .the majority of the folks that have worked and QSLed me (close to 250
- ) have been using either the Arrow or ELK based upon the information
on their cards. So they are popular. Are they optimum ? A lot of anecdotal information would seem to say NO . . .
Thirty-five years ago I worked Oscar 6 with a homebrew 2 mtr yagi that probably was worse than either the Arrow or Elk but I worked YV and KL7 from Indiana on CW with about 15 watts to the 3 elements which my XYL waved around at my directions . . . not any more . . .what do I use these days : a pair of circular polarity yagis on 10 foot booms manufactured by M Square . . . .
Folks ask what should they buy ? Maybe a Ford or maybe a Chevy . . . neither is a Cadillac . . . .
Jim W9VNE _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
-- Trey -- N5THX
They who can give up essential liberty to obtain a little temporary safety, deserve neither liberty nor safety.
- Benjamin Franklin
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
__________ Information from ESET NOD32 Antivirus, version of virus signature database 3719 (20081227) __________
The message was checked by ESET NOD32 Antivirus.
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The message was checked by ESET NOD32 Antivirus.
Mr. Mc Bride,
Thank you for this post. It led me to a Google search, which provide a great starting point to go along with Item No. 3 in your post. It is:
http://www.dxzone.com/catalog/Software/Antenna_analysis/
Thank you again,
Tim - N3TL -------------- Original message from "Art McBride" [email protected]: --------------
To All,
- Amateur Radio is learning by doing.
- A large amount of data on Yagi type antennas exists, easily found, and is
well proven. 3. Several design programs for antennas exist reducing construction time and waist of materials. 4. Equipment to measure comparative antenna performance at VHF/UHF frequencies is not hard to find.
Why do we line the pockets of some poorly designed antenna manufacturing companies instead of learning how and making the best performing antennas for our own use? If we do not learn these skills, no one will be left to teach and the skills will be lost.
There are many older Amateurs willing to teach those that want to learn, and hopefully many of those wanting to learn are at least one half of the age of those who can teach!
Art, KC6UQH
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Jim Danehy Sent: Saturday, December 27, 2008 6:33 PM To: [email protected] Subject: [amsat-bb] Fw: ELK or ARROW
. there is the old adage that you get what you pay for . . . why buy a poorly designed antenna that does not work very well
?
If you have a 5 element yagi that only produces 4 dbi you are not getting
what you paid for . . . most 2 element yagis would out perform that statistic . . . a 5 element yagi should be at least 9 db + or 10 db dbd (dipole ) not isotropic . . . . there is something that is called MERCHANTABILITY . . .i.e., an IMPLIED WARRANTY that you are getting at least the minimum for your money . . . 4 dbi for an Arrow is way off base . . . so it is not just ; you can not afford a Cadillac but you are not even getting a Ford or Chevy . . i.e.,
the gain of a 5 element yagi on 435 mhz . . . that is the issue, not cost
alone . . . . . . same comments apply to the ELK but I have attempted to make the point that there is a minimum performance for a certain number of
elements that is pretty OBJECTIVE and when it is not met . . . . well that is my point . . . these two antennas have shown to some testers that they do not measure up to the minimum EXPECTATIONS . . .unfortunately that
is acceptable to some . . . . then it becomes acceptable to many . . . and objectivity is abandoned . . .
Jim W9VNE
----- Original Message ----- From: "Trey Brown" To: "Jim Danehy" Sent: Saturday, December 27, 2008 6:39 PM Subject: Re: [amsat-bb] ELK or ARROW
Thanks for the comments. Realize, though, that not everyone wants or can afford to have the Cadillac.
On Sat, Dec 27, 2008 at 4:06 PM, Jim Danehy wrote:
the Arrow antenna has been critiqued by Kent Britain, WA5VJB
http://wa5vjb.com/references/Cheap%20Antennas-LEOs.pdf
he says that some have measured the Arrow for gain on 435 mhz @ 4 dbi (isotropic) . . . . and that further analysis showed that for the element lengths used on 435 mhz that it peaks at 457 mhz and not 435 mhz
. . . Kent is a well respected VHF/UHF antenna person who has plenty of credibility . . .
Kent opines that the Arrow, as built does not have its elements insulated from the boom. It uses dimensions for insulated elements . . .
so much for the Arrow . . . .
Now for the ELK : a local friend of mine owns an Arrow and he uses it successfully. He bought an ELK and attempted to compare the Arrow and the ELK . . . . he could not make an across town QSO on 435 mhz from his
second story window with the ELK , so he sent the ELK back for a refund .
I have worked and exchanged QSLs with several hundred satellite users . . .the majority of the folks that have worked and QSLed me (close to 250
- ) have been using either the Arrow or ELK based upon the information
on their cards. So they are popular. Are they optimum ? A lot of anecdotal information would seem to say NO . . .
Thirty-five years ago I worked Oscar 6 with a homebrew 2 mtr yagi that probably was worse than either the Arrow or Elk but I worked YV and KL7 from Indiana on CW with about 15 watts to the 3 elements which my XYL waved around at my directions . . . not any more . . .what do I use these days : a pair of circular polarity yagis on 10 foot booms manufactured by M Square . . . .
Folks ask what should they buy ? Maybe a Ford or maybe a Chevy . . . neither is a Cadillac . . . .
Jim W9VNE _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
-- Trey -- N5THX
They who can give up essential liberty to obtain a little temporary safety, deserve neither liberty nor safety.
- Benjamin Franklin
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
__________ Information from ESET NOD32 Antivirus, version of virus signature database 3719 (20081227) __________
The message was checked by ESET NOD32 Antivirus.
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The message was checked by ESET NOD32 Antivirus.
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Jim,
I don't believe Arrow publishes gain numbers for its handheld yagi. I'm confident someone will correct me if I'm wrong about that, and even provide the numbers.
Elk does - its Web site includes the following for the Model 2M/440L5 that I use:
2M Gain 6.8 dbd (8.9 dBi) 440 Gain 7 dBd (9 dBi)
Please help me to understand how the same comments you made about the Arrow apply to the Elk. What should the numbers be for that antenna?
Thank you in advance,
Tim -------------- Original message from "Jim Danehy" [email protected]: --------------
. there is the old adage that you get what you pay for . . . why buy a poorly designed antenna that does not work very well
?
If you have a 5 element yagi that only produces 4 dbi you are not getting what you paid for . . . most 2 element yagis would out perform that statistic . . . a 5 element yagi should be at least 9 db + or 10 db dbd (dipole ) not isotropic . . . . there is something that is called MERCHANTABILITY . . .i.e., an IMPLIED WARRANTY that you are getting at least the minimum for your money . . . 4 dbi for an Arrow is way off base . . . so it is not just ; you can not afford a Cadillac but you are not even getting a Ford or Chevy . . i.e., the gain of a 5 element yagi on 435 mhz . . . that is the issue, not cost alone . . . . . . same comments apply to the ELK but I have attempted to make the point that there is a minimum performance for a certain number of elements that is pretty OBJECTIVE and when it is not met . . . . well that is my point . . . these two antennas have shown to some testers that they do not measure up to the minimum EXPECTATIONS . . .unfortunately that is acceptable to some . . . . then it becomes acceptable to many . . . and objectivity is abandoned . . .
Jim W9VNE
----- Original Message ----- From: "Trey Brown" To: "Jim Danehy" Sent: Saturday, December 27, 2008 6:39 PM Subject: Re: [amsat-bb] ELK or ARROW
Thanks for the comments. Realize, though, that not everyone wants or can afford to have the Cadillac.
On Sat, Dec 27, 2008 at 4:06 PM, Jim Danehy wrote:
the Arrow antenna has been critiqued by Kent Britain, WA5VJB
http://wa5vjb.com/references/Cheap%20Antennas-LEOs.pdf
he says that some have measured the Arrow for gain on 435 mhz @ 4 dbi (isotropic) . . . . and that further analysis showed that for the element lengths used on 435 mhz that it peaks at 457 mhz and not 435 mhz . . . Kent is a well respected VHF/UHF antenna person who has plenty of credibility . . .
Kent opines that the Arrow, as built does not have its elements insulated from the boom. It uses dimensions for insulated elements . . . so much for the Arrow . . . .
Now for the ELK : a local friend of mine owns an Arrow and he uses it successfully. He bought an ELK and attempted to compare the Arrow and the ELK . . . . he could not make an across town QSO on 435 mhz from his second story window with the ELK , so he sent the ELK back for a refund .
I have worked and exchanged QSLs with several hundred satellite users . . .the majority of the folks that have worked and QSLed me (close to 250
- ) have been using either the Arrow or ELK based upon the information
on their cards. So they are popular. Are they optimum ? A lot of anecdotal information would seem to say NO . . .
Thirty-five years ago I worked Oscar 6 with a homebrew 2 mtr yagi that probably was worse than either the Arrow or Elk but I worked YV and KL7 from Indiana on CW with about 15 watts to the 3 elements which my XYL waved around at my directions . . . not any more . . .what do I use these days : a pair of circular polarity yagis on 10 foot booms manufactured by M Square . . . .
Folks ask what should they buy ? Maybe a Ford or maybe a Chevy . . . neither is a Cadillac . . . .
Jim W9VNE _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
-- Trey -- N5THX
They who can give up essential liberty to obtain a little temporary safety, deserve neither liberty nor safety.
- Benjamin Franklin
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Has anyone played with insulating the Arrow elements from the boom? It shouldn't be too hard to do.
73, Joe kk0sd
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Jim Danehy Sent: Saturday, December 27, 2008 8:33 PM To: [email protected] Subject: [amsat-bb] Fw: ELK or ARROW
there is the old adage that you get what you pay for . . . why buy a poorly designed antenna that does not work very well
?
If you have a 5 element yagi that only produces 4 dbi you are not getting
what you paid for . . . most 2 element yagis would out perform that statistic . . . a 5 element yagi should be at least 9 db + or 10 db dbd (dipole ) not isotropic . . . . there is something that is called MERCHANTABILITY . . .i.e., an IMPLIED WARRANTY that you are getting at least the minimum for your money . . . 4 dbi for an Arrow is way off base . . . so it is not just ; you can not afford a Cadillac but you are not even getting a Ford or Chevy . . i.e.,
the gain of a 5 element yagi on 435 mhz . . . that is the issue, not cost
alone . . . . . . same comments apply to the ELK but I have attempted to make the point that there is a minimum performance for a certain number of
elements that is pretty OBJECTIVE and when it is not met . . . . well that is my point . . . these two antennas have shown to some testers that they do not measure up to the minimum EXPECTATIONS . . .unfortunately that
is acceptable to some . . . . then it becomes acceptable to many . . . and objectivity is abandoned . . .
Jim W9VNE
----- Original Message ----- From: "Trey Brown" [email protected] To: "Jim Danehy" [email protected] Sent: Saturday, December 27, 2008 6:39 PM Subject: Re: [amsat-bb] ELK or ARROW
Thanks for the comments. Realize, though, that not everyone wants or can afford to have the Cadillac.
On Sat, Dec 27, 2008 at 4:06 PM, Jim Danehy [email protected] wrote:
the Arrow antenna has been critiqued by Kent Britain, WA5VJB
http://wa5vjb.com/references/Cheap%20Antennas-LEOs.pdf
he says that some have measured the Arrow for gain on 435 mhz @ 4 dbi (isotropic) . . . . and that further analysis showed that for the element lengths used on 435 mhz that it peaks at 457 mhz and not 435 mhz
. . . Kent is a well respected VHF/UHF antenna person who has plenty of credibility . . .
Kent opines that the Arrow, as built does not have its elements insulated from the boom. It uses dimensions for insulated elements . . .
so much for the Arrow . . . .
Now for the ELK : a local friend of mine owns an Arrow and he uses it successfully. He bought an ELK and attempted to compare the Arrow and the ELK . . . . he could not make an across town QSO on 435 mhz from his
second story window with the ELK , so he sent the ELK back for a refund .
I have worked and exchanged QSLs with several hundred satellite users . . .the majority of the folks that have worked and QSLed me (close to 250
- ) have been using either the Arrow or ELK based upon the information
on their cards. So they are popular. Are they optimum ? A lot of anecdotal information would seem to say NO . . .
Thirty-five years ago I worked Oscar 6 with a homebrew 2 mtr yagi that probably was worse than either the Arrow or Elk but I worked YV and KL7 from Indiana on CW with about 15 watts to the 3 elements which my XYL waved around at my directions . . . not any more . . .what do I use these days : a pair of circular polarity yagis on 10 foot booms manufactured by M Square . . . .
Folks ask what should they buy ? Maybe a Ford or maybe a Chevy . . . neither is a Cadillac . . . .
Jim W9VNE _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
-- Trey -- N5THX
They who can give up essential liberty to obtain a little temporary safety, deserve neither liberty nor safety.
- Benjamin Franklin
_______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Or you can just lengthen them 1/4" on a side with a threaded spacer.... Jim KQ6EA
--- On Sat, 12/27/08, Gary "Joe" Mayfield [email protected] wrote:
From: Gary "Joe" Mayfield [email protected] Subject: [amsat-bb] Re: Fw: ELK or ARROW To: [email protected] Date: Saturday, December 27, 2008, 8:17 PM Has anyone played with insulating the Arrow elements from the boom? It shouldn't be too hard to do.
73, Joe kk0sd
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Jim Danehy Sent: Saturday, December 27, 2008 8:33 PM To: [email protected] Subject: [amsat-bb] Fw: ELK or ARROW
there is the old adage that you get what you pay for . . . why buy a poorly designed antenna that does not work very well
?
If you have a 5 element yagi that only produces 4 dbi
you are not getting
what you paid for . . . most 2 element yagis would out
perform that
statistic . . . a 5 element yagi should be at least 9
db + or 10 db dbd
(dipole ) not isotropic . . . . there is something
that is called
MERCHANTABILITY . . .i.e., an IMPLIED WARRANTY that
you are getting at
least the minimum for your money . . . 4 dbi for an Arrow is way off base . . . so it is not
just ; you can not
afford a Cadillac but you are not even getting a Ford
or Chevy . . i.e.,
the gain of a 5 element yagi on 435 mhz . . . that is
the issue, not cost
alone . . . . . . same comments apply to the ELK but I
have attempted to
make the point that there is a minimum performance for
a certain number of
elements that is pretty OBJECTIVE and when it is not
met . . . . well
that is my point . . . these two antennas have shown
to some testers that
they do not measure up to the minimum EXPECTATIONS . .
.unfortunately that
is acceptable to some . . . . then it becomes
acceptable to many . . .
and objectivity is abandoned . . .
Jim W9VNE
----- Original Message ----- From: "Trey Brown"
To: "Jim Danehy"
Sent: Saturday, December 27, 2008 6:39 PM Subject: Re: [amsat-bb] ELK or ARROW
Thanks for the comments. Realize, though, that not
everyone wants or
can afford to have the Cadillac.
On Sat, Dec 27, 2008 at 4:06 PM, Jim Danehy
[email protected] wrote:
the Arrow antenna has been critiqued by Kent
Britain, WA5VJB
http://wa5vjb.com/references/Cheap%20Antennas-LEOs.pdf
he says that some have measured the Arrow for
gain on 435 mhz @ 4 dbi
(isotropic) . . . . and that further analysis
showed that for the
element lengths used on 435 mhz that it peaks
at 457 mhz and not 435 mhz
. . . Kent is a well respected VHF/UHF antenna
person who has plenty of
credibility . . .
Kent opines that the Arrow, as built does not
have its elements
insulated from the boom. It uses dimensions
for insulated elements . . .
so much for the Arrow . . . .
Now for the ELK : a local friend of mine owns
an Arrow and he uses it
successfully. He bought an ELK and attempted
to compare the Arrow and
the ELK . . . . he could not make an across
town QSO on 435 mhz from his
second story window with the ELK , so he sent
the ELK back for a refund
.
I have worked and exchanged QSLs with several
hundred satellite users .
. .the majority of the folks that have worked
and QSLed me (close to 250
- ) have been using either the Arrow or ELK
based upon the information
on their cards. So they are popular. Are they
optimum ? A lot of
anecdotal information would seem to say NO . .
.
Thirty-five years ago I worked Oscar 6 with a
homebrew 2 mtr yagi that
probably was worse than either the Arrow or
Elk but I worked YV and KL7
from Indiana on CW with about 15 watts to the
3 elements which my XYL
waved around at my directions . . . not any
more . . .what do I use
these days : a pair of circular polarity yagis
on 10 foot booms
manufactured by M Square . . . .
Folks ask what should they buy ? Maybe a Ford
or maybe a Chevy . . .
neither is a Cadillac . . . .
Jim W9VNE
Sent via [email protected]. Opinions
expressed are those of the author.
Not an AMSAT-NA member? Join now to support
the amateur satellite
program! Subscription settings:
http://amsat.org/mailman/listinfo/amsat-bb
-- Trey -- N5THX
They who can give up essential liberty to obtain a
little temporary
safety, deserve neither liberty nor safety.
- Benjamin Franklin
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Is it really worth it for .3 DB gain? Seems you would be better served by not using the diplexer.
Reference http://www.csvhfs.org/ant/CSANT06.HTML
I continue to be amazed how people can judge by just looking at imagined numbers. Seems that practical hands on experience has no bearing on how good or bad the Arrow or the Elk antenna is, but just conjecture over assumed specifications makes them less than a 'Ford or Chevy'?
If you need a handheld satellite antenna, you have pretty much 3 choices: -The 'bad' Arrow -The equally 'bad' Elk -make your own Arrow clone, which according to the numbers is far superior (what's that they say about imitation?)
I have an Arrow and have 'field tested' the Elk. I stuck with the Arrow. My OPINION, it's better. Others disagree. I contemplated building an Arrow clone, as there are several websites that tell you how. Are they better? Perhaps, but I got to think that a DB or 2 won't make that much difference.
Believe what you want, but I believe the Arrow works just fine the way it it is.
Jim Bob Buckeye AKA **** Jim Leder**** K8CXM since 1961 IBM retiree since 1999
There are 10 types of people in this world -- those who understand binary and those who don't.
----- Original Message ----- From: "Jim Jerzycke" [email protected] To: [email protected]; "Gary Joe Mayfield" [email protected] Sent: Saturday, December 27, 2008 11:42 PM Subject: [amsat-bb] Re: Fw: ELK or ARROW
Or you can just lengthen them 1/4" on a side with a threaded spacer.... Jim KQ6EA
--- On Sat, 12/27/08, Gary "Joe" Mayfield [email protected] wrote:
From: Gary "Joe" Mayfield [email protected] Subject: [amsat-bb] Re: Fw: ELK or ARROW To: [email protected] Date: Saturday, December 27, 2008, 8:17 PM Has anyone played with insulating the Arrow elements from the boom? It shouldn't be too hard to do.
73, Joe kk0sd
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Jim Danehy Sent: Saturday, December 27, 2008 8:33 PM To: [email protected] Subject: [amsat-bb] Fw: ELK or ARROW
there is the old adage that you get what you pay for . . . why buy a poorly designed antenna that does not work very well
?
If you have a 5 element yagi that only produces 4 dbi
you are not getting
what you paid for . . . most 2 element yagis would out
perform that
statistic . . . a 5 element yagi should be at least 9
db + or 10 db dbd
(dipole ) not isotropic . . . . there is something
that is called
MERCHANTABILITY . . .i.e., an IMPLIED WARRANTY that
you are getting at
least the minimum for your money . . . 4 dbi for an Arrow is way off base . . . so it is not
just ; you can not
afford a Cadillac but you are not even getting a Ford
or Chevy . . i.e.,
the gain of a 5 element yagi on 435 mhz . . . that is
the issue, not cost
alone . . . . . . same comments apply to the ELK but I
have attempted to
make the point that there is a minimum performance for
a certain number of
elements that is pretty OBJECTIVE and when it is not
met . . . . well
that is my point . . . these two antennas have shown
to some testers that
they do not measure up to the minimum EXPECTATIONS . .
.unfortunately that
is acceptable to some . . . . then it becomes
acceptable to many . . .
and objectivity is abandoned . . .
Jim W9VNE
----- Original Message ----- From: "Trey Brown"
To: "Jim Danehy"
Sent: Saturday, December 27, 2008 6:39 PM Subject: Re: [amsat-bb] ELK or ARROW
Thanks for the comments. Realize, though, that not
everyone wants or
can afford to have the Cadillac.
On Sat, Dec 27, 2008 at 4:06 PM, Jim Danehy
[email protected] wrote:
the Arrow antenna has been critiqued by Kent
Britain, WA5VJB
http://wa5vjb.com/references/Cheap%20Antennas-LEOs.pdf
he says that some have measured the Arrow for
gain on 435 mhz @ 4 dbi
(isotropic) . . . . and that further analysis
showed that for the
element lengths used on 435 mhz that it peaks
at 457 mhz and not 435 mhz
. . . Kent is a well respected VHF/UHF antenna
person who has plenty of
credibility . . .
Kent opines that the Arrow, as built does not
have its elements
insulated from the boom. It uses dimensions
for insulated elements . . .
so much for the Arrow . . . .
Now for the ELK : a local friend of mine owns
an Arrow and he uses it
successfully. He bought an ELK and attempted
to compare the Arrow and
the ELK . . . . he could not make an across
town QSO on 435 mhz from his
second story window with the ELK , so he sent
the ELK back for a refund
.
I have worked and exchanged QSLs with several
hundred satellite users .
. .the majority of the folks that have worked
and QSLed me (close to 250
- ) have been using either the Arrow or ELK
based upon the information
on their cards. So they are popular. Are they
optimum ? A lot of
anecdotal information would seem to say NO . .
.
Thirty-five years ago I worked Oscar 6 with a
homebrew 2 mtr yagi that
probably was worse than either the Arrow or
Elk but I worked YV and KL7
from Indiana on CW with about 15 watts to the
3 elements which my XYL
waved around at my directions . . . not any
more . . .what do I use
these days : a pair of circular polarity yagis
on 10 foot booms
manufactured by M Square . . . .
Folks ask what should they buy ? Maybe a Ford
or maybe a Chevy . . .
neither is a Cadillac . . . .
Jim W9VNE
Sent via [email protected]. Opinions
expressed are those of the author.
Not an AMSAT-NA member? Join now to support
the amateur satellite
program! Subscription settings:
http://amsat.org/mailman/listinfo/amsat-bb
-- Trey -- N5THX
They who can give up essential liberty to obtain a
little temporary
safety, deserve neither liberty nor safety.
- Benjamin Franklin
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
This whole "car talk" line of reasoning set me to wondering ... because I'm confident there are "lemon" antennas just like there are autos.
I've been wondering whether your Elk was a lemon, or whether my Arrow was - and also whether your Arrow is a "good one" and my Elk is a "good one." I guess we'll never know.
I couldn't agree with you more about the importance of hands-on experience. It's why you stuck with you Arrow and I with my Elk - they work for us, respectively.
For HT operation only, there are some whips that do, indeed, work the satellites. My experience here is that 10 degrees is about the limit for getting into one with a whip like the Pryme AL800 or te Diamond RH-789, but the latter receives here very well - better than I expected. Each sells for about $35 from HRO. N5AFV has made thousands of contacts using the AL800.
Hope to hear you on the air again soon!
Tim - N3TL -------------- Original message from "Jim Leder" [email protected]: --------------
Is it really worth it for .3 DB gain? Seems you would be better served by not using the diplexer.
Reference http://www.csvhfs.org/ant/CSANT06.HTML
I continue to be amazed how people can judge by just looking at imagined numbers. Seems that practical hands on experience has no bearing on how good or bad the Arrow or the Elk antenna is, but just conjecture over assumed specifications makes them less than a 'Ford or Chevy'?
If you need a handheld satellite antenna, you have pretty much 3 choices: -The 'bad' Arrow -The equally 'bad' Elk -make your own Arrow clone, which according to the numbers is far superior (what's that they say about imitation?)
I have an Arrow and have 'field tested' the Elk. I stuck with the Arrow. My OPINION, it's better. Others disagree. I contemplated building an Arrow clone, as there are several websites that tell you how. Are they better? Perhaps, but I got to think that a DB or 2 won't make that much difference.
Believe what you want, but I believe the Arrow works just fine the way it it is.
Jim Bob Buckeye AKA **** Jim Leder**** K8CXM since 1961 IBM retiree since 1999
There are 10 types of people in this world -- those who understand binary and those who don't.
----- Original Message ----- From: "Jim Jerzycke" To: ; "Gary Joe Mayfield" Sent: Saturday, December 27, 2008 11:42 PM Subject: [amsat-bb] Re: Fw: ELK or ARROW
Or you can just lengthen them 1/4" on a side with a threaded spacer.... Jim KQ6EA
--- On Sat, 12/27/08, Gary "Joe" Mayfield wrote:
From: Gary "Joe" Mayfield Subject: [amsat-bb] Re: Fw: ELK or ARROW To: [email protected] Date: Saturday, December 27, 2008, 8:17 PM Has anyone played with insulating the Arrow elements from the boom? It shouldn't be too hard to do.
73, Joe kk0sd
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Jim Danehy Sent: Saturday, December 27, 2008 8:33 PM To: [email protected] Subject: [amsat-bb] Fw: ELK or ARROW
there is the old adage that you get what you pay for . . . why buy a poorly designed antenna that does not work very well
?
If you have a 5 element yagi that only produces 4 dbi
you are not getting
what you paid for . . . most 2 element yagis would out
perform that
statistic . . . a 5 element yagi should be at least 9
db + or 10 db dbd
(dipole ) not isotropic . . . . there is something
that is called
MERCHANTABILITY . . .i.e., an IMPLIED WARRANTY that
you are getting at
least the minimum for your money . . . 4 dbi for an Arrow is way off base . . . so it is not
just ; you can not
afford a Cadillac but you are not even getting a Ford
or Chevy . . i.e.,
the gain of a 5 element yagi on 435 mhz . . . that is
the issue, not cost
alone . . . . . . same comments apply to the ELK but I
have attempted to
make the point that there is a minimum performance for
a certain number of
elements that is pretty OBJECTIVE and when it is not
met . . . . well
that is my point . . . these two antennas have shown
to some testers that
they do not measure up to the minimum EXPECTATIONS . .
.unfortunately that
is acceptable to some . . . . then it becomes
acceptable to many . . .
and objectivity is abandoned . . .
Jim W9VNE
----- Original Message ----- From: "Trey Brown"
To: "Jim Danehy"
Sent: Saturday, December 27, 2008 6:39 PM Subject: Re: [amsat-bb] ELK or ARROW
Thanks for the comments. Realize, though, that not
everyone wants or
can afford to have the Cadillac.
On Sat, Dec 27, 2008 at 4:06 PM, Jim Danehy
wrote:
the Arrow antenna has been critiqued by Kent
Britain, WA5VJB
http://wa5vjb.com/references/Cheap%20Antennas-LEOs.pdf
he says that some have measured the Arrow for
gain on 435 mhz @ 4 dbi
(isotropic) . . . . and that further analysis
showed that for the
element lengths used on 435 mhz that it peaks
at 457 mhz and not 435 mhz
. . . Kent is a well respected VHF/UHF antenna
person who has plenty of
credibility . . .
Kent opines that the Arrow, as built does not
have its elements
insulated from the boom. It uses dimensions
for insulated elements . . .
so much for the Arrow . . . .
Now for the ELK : a local friend of mine owns
an Arrow and he uses it
successfully. He bought an ELK and attempted
to compare the Arrow and
the ELK . . . . he could not make an across
town QSO on 435 mhz from his
second story window with the ELK , so he sent
the ELK back for a refund
.
I have worked and exchanged QSLs with several
hundred satellite users .
. .the majority of the folks that have worked
and QSLed me (close to 250
- ) have been using either the Arrow or ELK
based upon the information
on their cards. So they are popular. Are they
optimum ? A lot of
anecdotal information would seem to say NO . .
.
Thirty-five years ago I worked Oscar 6 with a
homebrew 2 mtr yagi that
probably was worse than either the Arrow or
Elk but I worked YV and KL7
from Indiana on CW with about 15 watts to the
3 elements which my XYL
waved around at my directions . . . not any
more . . .what do I use
these days : a pair of circular polarity yagis
on 10 foot booms
manufactured by M Square . . . .
Folks ask what should they buy ? Maybe a Ford
or maybe a Chevy . . .
neither is a Cadillac . . . .
Jim W9VNE
Sent via [email protected]. Opinions
expressed are those of the author.
Not an AMSAT-NA member? Join now to support
the amateur satellite
program! Subscription settings:
http://amsat.org/mailman/listinfo/amsat-bb
-- Trey -- N5THX
They who can give up essential liberty to obtain a
little temporary
safety, deserve neither liberty nor safety.
- Benjamin Franklin
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
http://www.csvhfs.org/ant/CSANT06.HTML
Man; that is some good info. I have nothing but respect for Kent, wa5vjb. Would someone please clarify some things for me?
1. Arrow Antenna w/8-32 nuts on elements ~7.3 2. Arrow Antenna w/plastic inserts on elements ~7.3 3. Arrow Antenna w/star washers on elements ~7.1 4. Arrow Antenna w/o Diplexer ~7.0 5. Arrow Antenna w/"torqued" elements ~7.0 6. Arrow Antenna w/Diplexer ~4.6
I assume number 6 is the dual band Arrow "out of the box", and that number 4 is the dual band Arrow "out of the box" bypassing the diplexer. Is this correct?
Does everyone else read this as insulating the elements, and/or lengthening the elements only buys you at most .3 dB, or were those tests run with the diplexer in line?
It seems improving the 2.4 dB of insertion loss of the diplexer would be a better strategy (although not necessarily easy in the space available) than attempting to modify what is very mechanically sound antenna.
73, Joe kk0sd
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Jim Leder Sent: Sunday, December 28, 2008 8:06 AM To: Amsat Subject: [amsat-bb] Re: Fw: ELK or ARROW
Is it really worth it for .3 DB gain? Seems you would be better served by not using the diplexer.
Reference http://www.csvhfs.org/ant/CSANT06.HTML
I continue to be amazed how people can judge by just looking at imagined numbers. Seems that practical hands on experience has no bearing on how good
or bad the Arrow or the Elk antenna is, but just conjecture over assumed specifications makes them less than a 'Ford or Chevy'?
If you need a handheld satellite antenna, you have pretty much 3 choices: -The 'bad' Arrow -The equally 'bad' Elk -make your own Arrow clone, which according to the numbers is far superior (what's that they say about imitation?)
I have an Arrow and have 'field tested' the Elk. I stuck with the Arrow. My OPINION, it's better. Others disagree. I contemplated building an Arrow clone, as there are several websites that tell you how. Are they better? Perhaps, but I got to think that a DB or 2 won't make that much difference.
Believe what you want, but I believe the Arrow works just fine the way it it is.
Jim Bob Buckeye AKA **** Jim Leder**** K8CXM since 1961 IBM retiree since 1999
There are 10 types of people in this world -- those who understand binary and those who don't.
----- Original Message ----- From: "Jim Jerzycke" [email protected] To: [email protected]; "Gary Joe Mayfield" [email protected] Sent: Saturday, December 27, 2008 11:42 PM Subject: [amsat-bb] Re: Fw: ELK or ARROW
Or you can just lengthen them 1/4" on a side with a threaded spacer.... Jim KQ6EA
--- On Sat, 12/27/08, Gary "Joe" Mayfield [email protected] wrote:
From: Gary "Joe" Mayfield [email protected] Subject: [amsat-bb] Re: Fw: ELK or ARROW To: [email protected] Date: Saturday, December 27, 2008, 8:17 PM Has anyone played with insulating the Arrow elements from the boom? It shouldn't be too hard to do.
73, Joe kk0sd
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Jim Danehy Sent: Saturday, December 27, 2008 8:33 PM To: [email protected] Subject: [amsat-bb] Fw: ELK or ARROW
there is the old adage that you get what you pay for . . . why buy a poorly designed antenna that does not work very well
?
If you have a 5 element yagi that only produces 4 dbi
you are not getting
what you paid for . . . most 2 element yagis would out
perform that
statistic . . . a 5 element yagi should be at least 9
db + or 10 db dbd
(dipole ) not isotropic . . . . there is something
that is called
MERCHANTABILITY . . .i.e., an IMPLIED WARRANTY that
you are getting at
least the minimum for your money . . . 4 dbi for an Arrow is way off base . . . so it is not
just ; you can not
afford a Cadillac but you are not even getting a Ford
or Chevy . . i.e.,
the gain of a 5 element yagi on 435 mhz . . . that is
the issue, not cost
alone . . . . . . same comments apply to the ELK but I
have attempted to
make the point that there is a minimum performance for
a certain number of
elements that is pretty OBJECTIVE and when it is not
met . . . . well
that is my point . . . these two antennas have shown
to some testers that
they do not measure up to the minimum EXPECTATIONS . .
.unfortunately that
is acceptable to some . . . . then it becomes
acceptable to many . . .
and objectivity is abandoned . . .
Jim W9VNE
----- Original Message ----- From: "Trey Brown"
To: "Jim Danehy"
Sent: Saturday, December 27, 2008 6:39 PM Subject: Re: [amsat-bb] ELK or ARROW
Thanks for the comments. Realize, though, that not
everyone wants or
can afford to have the Cadillac.
On Sat, Dec 27, 2008 at 4:06 PM, Jim Danehy
[email protected] wrote:
the Arrow antenna has been critiqued by Kent
Britain, WA5VJB
http://wa5vjb.com/references/Cheap%20Antennas-LEOs.pdf
he says that some have measured the Arrow for
gain on 435 mhz @ 4 dbi
(isotropic) . . . . and that further analysis
showed that for the
element lengths used on 435 mhz that it peaks
at 457 mhz and not 435 mhz
. . . Kent is a well respected VHF/UHF antenna
person who has plenty of
credibility . . .
Kent opines that the Arrow, as built does not
have its elements
insulated from the boom. It uses dimensions
for insulated elements . . .
so much for the Arrow . . . .
Now for the ELK : a local friend of mine owns
an Arrow and he uses it
successfully. He bought an ELK and attempted
to compare the Arrow and
the ELK . . . . he could not make an across
town QSO on 435 mhz from his
second story window with the ELK , so he sent
the ELK back for a refund
.
I have worked and exchanged QSLs with several
hundred satellite users .
. .the majority of the folks that have worked
and QSLed me (close to 250
- ) have been using either the Arrow or ELK
based upon the information
on their cards. So they are popular. Are they
optimum ? A lot of
anecdotal information would seem to say NO . .
.
Thirty-five years ago I worked Oscar 6 with a
homebrew 2 mtr yagi that
probably was worse than either the Arrow or
Elk but I worked YV and KL7
from Indiana on CW with about 15 watts to the
3 elements which my XYL
waved around at my directions . . . not any
more . . .what do I use
these days : a pair of circular polarity yagis
on 10 foot booms
manufactured by M Square . . . .
Folks ask what should they buy ? Maybe a Ford
or maybe a Chevy . . .
neither is a Cadillac . . . .
Jim W9VNE
Sent via [email protected]. Opinions
expressed are those of the author.
Not an AMSAT-NA member? Join now to support
the amateur satellite
program! Subscription settings:
http://amsat.org/mailman/listinfo/amsat-bb
-- Trey -- N5THX
They who can give up essential liberty to obtain a
little temporary
safety, deserve neither liberty nor safety.
- Benjamin Franklin
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
_______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
I guess CSVHF has already tested the Arrow at UHF - oops!
How I read Kent's data is that adding either an 8-32 nut to lenthen the elements #1, or insulate them #2 improves gain about 0.3 dB over the standard antenna #4. I'mnot sure what torquing means other than maybe consistent tightening each element. Obviously it does not show any difference with #4. #6 merely shows that using the diplexer adds some loss which is normal for any such device, though 2.4 dB seems a bit high (but maybe not for its small phycial size -compare its insertion loss with a Comet 416 diplexer).
In my opinion it is not fair to compare diplexer loss with antenna gain measurements. All diplexers have some losses as do repearer duplexers. One can merely compensate Tx power for this. Rx performance is harder to compensate but a preamp will help.
73, Ed - KL7UW
At 07:00 AM 12/28/2008, Gary "Joe" Mayfield wrote:
http://www.csvhfs.org/ant/CSANT06.HTML
Man; that is some good info. I have nothing but respect for Kent, wa5vjb. Would someone please clarify some things for me?
- Arrow Antenna w/8-32 nuts on elements ~7.3
- Arrow Antenna w/plastic inserts on elements ~7.3
- Arrow Antenna w/star washers on elements ~7.1
- Arrow Antenna w/o Diplexer ~7.0
- Arrow Antenna w/"torqued" elements ~7.0
- Arrow Antenna w/Diplexer ~4.6
I assume number 6 is the dual band Arrow "out of the box", and that number 4 is the dual band Arrow "out of the box" bypassing the diplexer. Is this correct?
Does everyone else read this as insulating the elements, and/or lengthening the elements only buys you at most .3 dB, or were those tests run with the diplexer in line?
It seems improving the 2.4 dB of insertion loss of the diplexer would be a better strategy (although not necessarily easy in the space available) than attempting to modify what is very mechanically sound antenna.
73, Joe kk0sd
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Jim Leder Sent: Sunday, December 28, 2008 8:06 AM To: Amsat Subject: [amsat-bb] Re: Fw: ELK or ARROW
Is it really worth it for .3 DB gain? Seems you would be better served by not using the diplexer.
Reference http://www.csvhfs.org/ant/CSANT06.HTML
I continue to be amazed how people can judge by just looking at imagined numbers. Seems that practical hands on experience has no bearing on how good
or bad the Arrow or the Elk antenna is, but just conjecture over assumed specifications makes them less than a 'Ford or Chevy'?
If you need a handheld satellite antenna, you have pretty much 3 choices: -The 'bad' Arrow -The equally 'bad' Elk -make your own Arrow clone, which according to the numbers is far superior (what's that they say about imitation?)
I have an Arrow and have 'field tested' the Elk. I stuck with the Arrow. My OPINION, it's better. Others disagree. I contemplated building an Arrow clone, as there are several websites that tell you how. Are they better? Perhaps, but I got to think that a DB or 2 won't make that much difference.
Believe what you want, but I believe the Arrow works just fine the way it it is.
Jim Bob Buckeye AKA**** Jim Leder**** K8CXM since 1961 IBM retiree since 1999
There are 10 types of people in this world -- those who understand binary and those who don't.
----- Original Message ----- From: "Jim Jerzycke" [email protected] To: [email protected]; "Gary Joe Mayfield" [email protected] Sent: Saturday, December 27, 2008 11:42 PM Subject: [amsat-bb] Re: Fw: ELK or ARROW
Or you can just lengthen them 1/4" on a side with a threaded spacer.... Jim KQ6EA
--- On Sat, 12/27/08, Gary "Joe" Mayfield [email protected] wrote:
From: Gary "Joe" Mayfield [email protected] Subject: [amsat-bb] Re: Fw: ELK or ARROW To: [email protected] Date: Saturday, December 27, 2008, 8:17 PM Has anyone played with insulating the Arrow elements from the boom? It shouldn't be too hard to do.
73, Joe kk0sd
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Jim Danehy Sent: Saturday, December 27, 2008 8:33 PM To: [email protected] Subject: [amsat-bb] Fw: ELK or ARROW
there is the old adage that you get what you pay for . . . why buy a poorly designed antenna that does not work very well
?
If you have a 5 element yagi that only produces 4 dbi
you are not getting
what you paid for . . . most 2 element yagis would out
perform that
statistic . . . a 5 element yagi should be at least 9
db + or 10 db dbd
(dipole ) not isotropic . . . . there is something
that is called
MERCHANTABILITY . . .i.e., an IMPLIED WARRANTY that
you are getting at
least the minimum for your money . . . 4 dbi for an Arrow is way off base . . . so it is not
just ; you can not
afford a Cadillac but you are not even getting a Ford
or Chevy . . i.e.,
the gain of a 5 element yagi on 435 mhz . . . that is
the issue, not cost
alone . . . . . . same comments apply to the ELK but I
have attempted to
make the point that there is a minimum performance for
a certain number of
elements that is pretty OBJECTIVE and when it is not
met . . . . well
that is my point . . . these two antennas have shown
to some testers that
they do not measure up to the minimum EXPECTATIONS . .
.unfortunately that
is acceptable to some . . . . then it becomes
acceptable to many . . .
and objectivity is abandoned . . .
Jim W9VNE
----- Original Message ----- From: "Trey Brown"
To: "Jim Danehy"
Sent: Saturday, December 27, 2008 6:39 PM Subject: Re: [amsat-bb] ELK or ARROW
Thanks for the comments. Realize, though, that not
everyone wants or
can afford to have the Cadillac.
On Sat, Dec 27, 2008 at 4:06 PM, Jim Danehy
[email protected] wrote:
the Arrow antenna has been critiqued by Kent
Britain, WA5VJB
http://wa5vjb.com/references/Cheap%20Antennas-LEOs.pdf
he says that some have measured the Arrow for
gain on 435 mhz @ 4 dbi
(isotropic) . . . . and that further analysis
showed that for the
element lengths used on 435 mhz that it peaks
at 457 mhz and not 435 mhz
. . . Kent is a well respected VHF/UHF antenna
person who has plenty of
credibility . . .
Kent opines that the Arrow, as built does not
have its elements
insulated from the boom. It uses dimensions
for insulated elements . . .
so much for the Arrow . . . .
Now for the ELK : a local friend of mine owns
an Arrow and he uses it
successfully. He bought an ELK and attempted
to compare the Arrow and
the ELK . . . . he could not make an across
town QSO on 435 mhz from his
second story window with the ELK , so he sent
the ELK back for a refund
.
I have worked and exchanged QSLs with several
hundred satellite users .
. .the majority of the folks that have worked
and QSLed me (close to 250
- ) have been using either the Arrow or ELK
based upon the information
on their cards. So they are popular. Are they
optimum ? A lot of
anecdotal information would seem to say NO . .
.
Thirty-five years ago I worked Oscar 6 with a
homebrew 2 mtr yagi that
probably was worse than either the Arrow or
Elk but I worked YV and KL7
from Indiana on CW with about 15 watts to the
3 elements which my XYL
waved around at my directions . . . not any
more . . .what do I use
these days : a pair of circular polarity yagis
on 10 foot booms
manufactured by M Square . . . .
Folks ask what should they buy ? Maybe a Ford
or maybe a Chevy . . .
neither is a Cadillac . . . .
Jim W9VNE
Sent via [email protected]. Opinions
expressed are those of the author.
Not an AMSAT-NA member? Join now to support
the amateur satellite
program! Subscription settings:
http://amsat.org/mailman/listinfo/amsat-bb
-- Trey -- N5THX
They who can give up essential liberty to obtain a
little temporary
safety, deserve neither liberty nor safety.
- Benjamin Franklin
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
I have had an Arrow for 8 years or so, and used in several years ago on UO-14 and AO-27 with my FT-817 with good contacts being made. I have also mounted the Arrow on my B5400 az-el rotator for use with these satellites and others briefly (only with 2m elements installed). I have taken the antenna to mountain-top locations to work 2m-SSB over 200-miles running with a 50w amp on 2m. I have used only the UHF elements for roving over 150-mile paths on 432. When using on only one band I didnot use the diplexer.
It seems to work quite well for its size. The antennas match well for SWR (but that does not say they are properly designed for optimum gain or pattern). I might take the dimensions and model them on my antenna sw to see what it says, but I am satisfied that the Arrow functions fine for its application.
How it measures up against other antennas of similar style/size I would not know. The best comparison would be to take all competitor antennas to the next CSVHF Conference and enter them into the antenna measurement program. The hams running them are quite experienced in making good field measurements of gain and pattern and the antennas would be fairly compared under exactly the same test conditions. In my mind that should settle all claims.
My current situation does not have my satellite antennas installed: M2-436CP42, LY2345, KLM-22C, 33-inch dish with helix feed (were used for AO-10/40). I have used a 19-inch mag-mount mobile antenna stuck to square of sheet metal to capture AO-51 telemetry using a 432 preamp, and am thinking about building up 2m&70cm Lindeblad's (sp?). I also have 2m halo that has only been used while mobile in the lower-48. I suspect that they might function OK on some Leos. I have a 7-element M2 2m yagi that might be used though it was bought for roving. It is probably a little high in gain for this (a 3-4 element yagi seems more appropriate for Leo work).
73 & HNY from Alaska! Ed - KL7UW
At 05:06 AM 12/28/2008, Jim Leder wrote:
Is it really worth it for .3 DB gain? Seems you would be better served by not using the diplexer.
Reference http://www.csvhfs.org/ant/CSANT06.HTML
I continue to be amazed how people can judge by just looking at imagined numbers. Seems that practical hands on experience has no bearing on how good or bad the Arrow or the Elk antenna is, but just conjecture over assumed specifications makes them less than a 'Ford or Chevy'?
If you need a handheld satellite antenna, you have pretty much 3 choices: -The 'bad' Arrow -The equally 'bad' Elk -make your own Arrow clone, which according to the numbers is far superior (what's that they say about imitation?)
I have an Arrow and have 'field tested' the Elk. I stuck with the Arrow. My OPINION, it's better. Others disagree. I contemplated building an Arrow clone, as there are several websites that tell you how. Are they better? Perhaps, but I got to think that a DB or 2 won't make that much difference.
Believe what you want, but I believe the Arrow works just fine the way it it is.
Jim Bob Buckeye AKA**** Jim Leder**** K8CXM since 1961 IBM retiree since 1999
There are 10 types of people in this world -- those who understand binary and those who don't.
----- Original Message ----- From: "Jim Jerzycke" [email protected] To: [email protected]; "Gary Joe Mayfield" [email protected] Sent: Saturday, December 27, 2008 11:42 PM Subject: [amsat-bb] Re: Fw: ELK or ARROW
Or you can just lengthen them 1/4" on a side with a threaded spacer.... Jim KQ6EA
--- On Sat, 12/27/08, Gary "Joe" Mayfield [email protected] wrote:
From: Gary "Joe" Mayfield [email protected] Subject: [amsat-bb] Re: Fw: ELK or ARROW To: [email protected] Date: Saturday, December 27, 2008, 8:17 PM Has anyone played with insulating the Arrow elements from the boom? It shouldn't be too hard to do.
73, Joe kk0sd
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Jim Danehy Sent: Saturday, December 27, 2008 8:33 PM To: [email protected] Subject: [amsat-bb] Fw: ELK or ARROW
there is the old adage that you get what you pay for . . . why buy a poorly designed antenna that does not work very well
?
If you have a 5 element yagi that only produces 4 dbi
you are not getting
what you paid for . . . most 2 element yagis would out
perform that
statistic . . . a 5 element yagi should be at least 9
db + or 10 db dbd
(dipole ) not isotropic . . . . there is something
that is called
MERCHANTABILITY . . .i.e., an IMPLIED WARRANTY that
you are getting at
least the minimum for your money . . . 4 dbi for an Arrow is way off base . . . so it is not
just ; you can not
afford a Cadillac but you are not even getting a Ford
or Chevy . . i.e.,
the gain of a 5 element yagi on 435 mhz . . . that is
the issue, not cost
alone . . . . . . same comments apply to the ELK but I
have attempted to
make the point that there is a minimum performance for
a certain number of
elements that is pretty OBJECTIVE and when it is not
met . . . . well
that is my point . . . these two antennas have shown
to some testers that
they do not measure up to the minimum EXPECTATIONS . .
.unfortunately that
is acceptable to some . . . . then it becomes
acceptable to many . . .
and objectivity is abandoned . . .
Jim W9VNE
----- Original Message ----- From: "Trey Brown"
To: "Jim Danehy"
Sent: Saturday, December 27, 2008 6:39 PM Subject: Re: [amsat-bb] ELK or ARROW
Thanks for the comments. Realize, though, that not
everyone wants or
can afford to have the Cadillac.
On Sat, Dec 27, 2008 at 4:06 PM, Jim Danehy
[email protected] wrote:
the Arrow antenna has been critiqued by Kent
Britain, WA5VJB
http://wa5vjb.com/references/Cheap%20Antennas-LEOs.pdf
he says that some have measured the Arrow for
gain on 435 mhz @ 4 dbi
(isotropic) . . . . and that further analysis
showed that for the
element lengths used on 435 mhz that it peaks
at 457 mhz and not 435 mhz
. . . Kent is a well respected VHF/UHF antenna
person who has plenty of
credibility . . .
Kent opines that the Arrow, as built does not
have its elements
insulated from the boom. It uses dimensions
for insulated elements . . .
so much for the Arrow . . . .
Now for the ELK : a local friend of mine owns
an Arrow and he uses it
successfully. He bought an ELK and attempted
to compare the Arrow and
the ELK . . . . he could not make an across
town QSO on 435 mhz from his
second story window with the ELK , so he sent
the ELK back for a refund
.
I have worked and exchanged QSLs with several
hundred satellite users .
. .the majority of the folks that have worked
and QSLed me (close to 250
- ) have been using either the Arrow or ELK
based upon the information
on their cards. So they are popular. Are they
optimum ? A lot of
anecdotal information would seem to say NO . .
.
Thirty-five years ago I worked Oscar 6 with a
homebrew 2 mtr yagi that
probably was worse than either the Arrow or
Elk but I worked YV and KL7
from Indiana on CW with about 15 watts to the
3 elements which my XYL
waved around at my directions . . . not any
more . . .what do I use
these days : a pair of circular polarity yagis
on 10 foot booms
manufactured by M Square . . . .
Folks ask what should they buy ? Maybe a Ford
or maybe a Chevy . . .
neither is a Cadillac . . . .
Jim W9VNE
Sent via [email protected]. Opinions
expressed are those of the author.
Not an AMSAT-NA member? Join now to support
the amateur satellite
program! Subscription settings:
http://amsat.org/mailman/listinfo/amsat-bb
-- Trey -- N5THX
They who can give up essential liberty to obtain a
little temporary
safety, deserve neither liberty nor safety.
- Benjamin Franklin
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
The issue is really application of the antenna. A poor antenna in this case is using one where it's not designed for. Just because something costs less does not mean it will NOT work in the application you have for it (double negative). For example a high gain boom antenna will work poorly as a handheld antenna due to it narrow beamwidth and in ability to point at target.
Case in point, we can all drive Suburban's because there is 10" of snow on the ground but why? A Camry will work just as well if all I need is to travel main highways.
I know that based on using the Arrow holding by hand it is better then a dipole so it at least better then about 2.15dbi and using it I know that I can get at least twice the RX power when pointed down it's boresite so it's about 3db of gain over the dipole (0 dBd). That would make it ABOUT 5 db.
I would like to see the plots of the patterns of the tests done on the arrow, also what the range looked like and equipment used. I have seen commercial antenna companies' mess up antenna measurements. Properly done engineering tests will align with what is experienced in the field, if it doesn't then its an oops. 4dBi would mean not much better then a wet noodle....
Point: The arrow works well for its application and is worth the money if your application is a handheld or simple tripod mounted antenna. I say it's is worth the money because it works.
73,
Dave Burnsville, MN WB7DRU; NNN0AXK
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Jim Danehy Sent: Saturday, December 27, 2008 8:35 PM To: [email protected] Subject: [amsat-bb] Fw: ELK or ARROW
. there is the old adage that you get what you pay for . . . why buy a poorly designed antenna that does not work very well
?
If you have a 5 element yagi that only produces 4 dbi you are not getting
what you paid for . . . most 2 element yagis would out perform that statistic . . . a 5 element yagi should be at least 9 db + or 10 db dbd (dipole ) not isotropic . . . . there is something that is called MERCHANTABILITY . . .i.e., an IMPLIED WARRANTY that you are getting at least the minimum for your money . . . 4 dbi for an Arrow is way off base . . . so it is not just ; you can not afford a Cadillac but you are not even getting a Ford or Chevy . . i.e.,
the gain of a 5 element yagi on 435 mhz . . . that is the issue, not cost
alone . . . . . . same comments apply to the ELK but I have attempted to make the point that there is a minimum performance for a certain number of
elements that is pretty OBJECTIVE and when it is not met . . . . well that is my point . . . these two antennas have shown to some testers that they do not measure up to the minimum EXPECTATIONS . . .unfortunately that
is acceptable to some . . . . then it becomes acceptable to many . . . and objectivity is abandoned . . .
Jim W9VNE
----- Original Message ----- From: "Trey Brown" [email protected] To: "Jim Danehy" [email protected] Sent: Saturday, December 27, 2008 6:39 PM Subject: Re: [amsat-bb] ELK or ARROW
Thanks for the comments. Realize, though, that not everyone wants or can afford to have the Cadillac.
On Sat, Dec 27, 2008 at 4:06 PM, Jim Danehy [email protected] wrote:
the Arrow antenna has been critiqued by Kent Britain, WA5VJB
http://wa5vjb.com/references/Cheap%20Antennas-LEOs.pdf
he says that some have measured the Arrow for gain on 435 mhz @ 4 dbi (isotropic) . . . . and that further analysis showed that for the element lengths used on 435 mhz that it peaks at 457 mhz and not 435 mhz
. . . Kent is a well respected VHF/UHF antenna person who has plenty of credibility . . .
Kent opines that the Arrow, as built does not have its elements insulated from the boom. It uses dimensions for insulated elements . . .
so much for the Arrow . . . .
Now for the ELK : a local friend of mine owns an Arrow and he uses it successfully. He bought an ELK and attempted to compare the Arrow and the ELK . . . . he could not make an across town QSO on 435 mhz from his
second story window with the ELK , so he sent the ELK back for a refund .
I have worked and exchanged QSLs with several hundred satellite users . . .the majority of the folks that have worked and QSLed me (close to 250
- ) have been using either the Arrow or ELK based upon the information
on their cards. So they are popular. Are they optimum ? A lot of anecdotal information would seem to say NO . . .
Thirty-five years ago I worked Oscar 6 with a homebrew 2 mtr yagi that probably was worse than either the Arrow or Elk but I worked YV and KL7 from Indiana on CW with about 15 watts to the 3 elements which my XYL waved around at my directions . . . not any more . . .what do I use these days : a pair of circular polarity yagis on 10 foot booms manufactured by M Square . . . .
Folks ask what should they buy ? Maybe a Ford or maybe a Chevy . . . neither is a Cadillac . . . .
Jim W9VNE _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
-- Trey -- N5THX
They who can give up essential liberty to obtain a little temporary safety, deserve neither liberty nor safety.
- Benjamin Franklin
_______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
--- Get FREE High Speed Internet from USFamily.Net! -- http://www.usfamily.net/mkt-freepromo.html ---
Hi all, It "works" is a relative term. An 8 cylinder car running on 5 cylinders still "works"
In the process of learning about antennas the fine points should include:
1. A good front to back ratio on the receive side to reduce ground noise. 2. The satellite band is very narrow so some sacrifice of front to back ratio for the 2 M side for an additional 1.5 dB of gain may help in marginal conditions. 3. Insulation of the boom to the elements will reduce losses, and lower frequency. If elements make good solid contact to the boom and are tuned to the right frequency this loss is very small. 4. Changes in conductivity of element to boom contact will cause performance to vary. 5. If there is any corrosion on any electrical contact area of the antenna, including boom to element contact, receiver blocking can occur. Avoid using dissimilar metals to prevent corrosion. 6. Most of the fun is finding solutions to these problems. Start by looking at how antennas are built. There are some very clever designs of antennas in the market place. Many of these problems have already had multiple solutions applied.
Art, KC6UQH
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of David Donaldson Sent: Saturday, December 27, 2008 10:24 PM To: [email protected] Subject: [amsat-bb] Re: Fw: ELK or ARROW
The issue is really application of the antenna. A poor antenna in this case is using one where it's not designed for. Just because something costs less does not mean it will NOT work in the application you have for it (double negative). For example a high gain boom antenna will work poorly as a handheld antenna due to it narrow beamwidth and in ability to point at target.
Case in point, we can all drive Suburban's because there is 10" of snow on the ground but why? A Camry will work just as well if all I need is to travel main highways.
I know that based on using the Arrow holding by hand it is better then a dipole so it at least better then about 2.15dbi and using it I know that I can get at least twice the RX power when pointed down it's boresite so it's about 3db of gain over the dipole (0 dBd). That would make it ABOUT 5 db.
I would like to see the plots of the patterns of the tests done on the arrow, also what the range looked like and equipment used. I have seen commercial antenna companies' mess up antenna measurements. Properly done engineering tests will align with what is experienced in the field, if it doesn't then its an oops. 4dBi would mean not much better then a wet noodle....
Point: The arrow works well for its application and is worth the money if your application is a handheld or simple tripod mounted antenna. I say it's is worth the money because it works.
73,
Dave Burnsville, MN WB7DRU; NNN0AXK
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Jim Danehy Sent: Saturday, December 27, 2008 8:35 PM To: [email protected] Subject: [amsat-bb] Fw: ELK or ARROW
. there is the old adage that you get what you pay for . . . why buy a poorly designed antenna that does not work very well
?
If you have a 5 element yagi that only produces 4 dbi you are not getting
what you paid for . . . most 2 element yagis would out perform that statistic . . . a 5 element yagi should be at least 9 db + or 10 db dbd (dipole ) not isotropic . . . . there is something that is called MERCHANTABILITY . . .i.e., an IMPLIED WARRANTY that you are getting at least the minimum for your money . . . 4 dbi for an Arrow is way off base . . . so it is not just ; you can not afford a Cadillac but you are not even getting a Ford or Chevy . . i.e.,
the gain of a 5 element yagi on 435 mhz . . . that is the issue, not cost
alone . . . . . . same comments apply to the ELK but I have attempted to make the point that there is a minimum performance for a certain number of
elements that is pretty OBJECTIVE and when it is not met . . . . well that is my point . . . these two antennas have shown to some testers that they do not measure up to the minimum EXPECTATIONS . . .unfortunately that
is acceptable to some . . . . then it becomes acceptable to many . . . and objectivity is abandoned . . .
Jim W9VNE
----- Original Message ----- From: "Trey Brown" [email protected] To: "Jim Danehy" [email protected] Sent: Saturday, December 27, 2008 6:39 PM Subject: Re: [amsat-bb] ELK or ARROW
Thanks for the comments. Realize, though, that not everyone wants or can afford to have the Cadillac.
On Sat, Dec 27, 2008 at 4:06 PM, Jim Danehy [email protected] wrote:
the Arrow antenna has been critiqued by Kent Britain, WA5VJB
http://wa5vjb.com/references/Cheap%20Antennas-LEOs.pdf
he says that some have measured the Arrow for gain on 435 mhz @ 4 dbi (isotropic) . . . . and that further analysis showed that for the element lengths used on 435 mhz that it peaks at 457 mhz and not 435 mhz
. . . Kent is a well respected VHF/UHF antenna person who has plenty of credibility . . .
Kent opines that the Arrow, as built does not have its elements insulated from the boom. It uses dimensions for insulated elements . . .
so much for the Arrow . . . .
Now for the ELK : a local friend of mine owns an Arrow and he uses it successfully. He bought an ELK and attempted to compare the Arrow and the ELK . . . . he could not make an across town QSO on 435 mhz from his
second story window with the ELK , so he sent the ELK back for a refund .
I have worked and exchanged QSLs with several hundred satellite users . . .the majority of the folks that have worked and QSLed me (close to 250
- ) have been using either the Arrow or ELK based upon the information
on their cards. So they are popular. Are they optimum ? A lot of anecdotal information would seem to say NO . . .
Thirty-five years ago I worked Oscar 6 with a homebrew 2 mtr yagi that probably was worse than either the Arrow or Elk but I worked YV and KL7 from Indiana on CW with about 15 watts to the 3 elements which my XYL waved around at my directions . . . not any more . . .what do I use these days : a pair of circular polarity yagis on 10 foot booms manufactured by M Square . . . .
Folks ask what should they buy ? Maybe a Ford or maybe a Chevy . . . neither is a Cadillac . . . .
Jim W9VNE _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
-- Trey -- N5THX
They who can give up essential liberty to obtain a little temporary safety, deserve neither liberty nor safety.
- Benjamin Franklin
_______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
--- Get FREE High Speed Internet from USFamily.Net! -- http://www.usfamily.net/mkt-freepromo.html ---
_______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
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participants (8)
-
Art McBride -
David Donaldson -
Edward Cole -
Gary "Joe" Mayfield -
Jim Danehy -
Jim Jerzycke -
Jim Leder -
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