greetings
I would like to report very poor reception of echo even with an 8 element yagi and an 18 Db preamp. I assume the downlink power is real flea power for battery charging or other testing.
After 2 years of pleading with amsat, the downlink power is still a mystery. It is not shown on the colaradosatellite telemetry graphs (TX B) or the amsat website, after repeated requests here and elsewhere I'll assume it is being held secret for some reason.
There has been a tremendous lack of technical reporting on ECHO.
I realize people are very busy but time should be taken to educate the amsat community.
73, patrick N2OEQ 32323
How about copying the telemetry yourself instead of asking someone else to do it for you. It's there whenever the digital transmitter is, and you can download software for free to decode it.
73, Drew KO4MA
----- Original Message ----- From: "McGrane" [email protected] To: "Amsat BB" [email protected] Sent: Friday, August 25, 2006 9:27 AM Subject: [amsat-bb] ECHO
greetings
I would like to report very poor reception of echo even with an 8 element yagi and an 18 Db preamp. I assume the downlink power is real flea power for battery charging or other testing.
After 2 years of pleading with amsat, the downlink power is still a mystery. It is not shown on the colaradosatellite telemetry graphs (TX B) or the amsat website, after repeated requests here and elsewhere I'll assume it is being held secret for some reason.
There has been a tremendous lack of technical reporting on ECHO.
I realize people are very busy but time should be taken to educate the amsat community.
73, patrick N2OEQ 32323
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
How's your noise floor. I have the same issue here. the 1/2 watt TX is barely enough when I'm at home (urban area) and due to a high noise floor. When I'm out in the country, I don't have problems hearing the 1/2 watt TX with the same arrow antenna setup. If this is a fixed setup, perhaps a bandpass cavity on the RX would work. I don't know how well this would work in satellite doppler but it's very effective at removing intermod on my fixed terrestrial APRS station.
73 de Pat --- KA9SCF Amsat #35741
On 8/25/06, McGrane [email protected] wrote:
greetings
I would like to report very poor reception of echo even with an 8 element yagi and an 18 Db preamp. I assume the downlink power is real flea power for battery charging or other testing.
After 2 years of pleading with amsat, the downlink power is still a mystery. It is not shown on the colaradosatellite telemetry graphs (TX B) or the amsat website, after repeated requests here and elsewhere I'll assume it is being held secret for some reason.
There has been a tremendous lack of technical reporting on ECHO.
I realize people are very busy but time should be taken to educate the amsat community.
73, patrick N2OEQ 32323
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
Just copied last AO-51 pass.
TXa is .3 watts TXb is .4 watts tx current draw is 800 mA panel output is 15.1 v, 1193.9 mA telemetry broadcast rate is every 10 seconds
All right there in the open for every one who wants to expend a little bit of effort to find.
73, Drew KO4MA
----- Original Message ----- From: "McGrane" [email protected] To: "Amsat BB" [email protected] Sent: Friday, August 25, 2006 9:27 AM Subject: [amsat-bb] ECHO
greetings
I would like to report very poor reception of echo even with an 8 element yagi and an 18 Db preamp. I assume the downlink power is real flea power for battery charging or other testing.
After 2 years of pleading with amsat, the downlink power is still a mystery. It is not shown on the colaradosatellite telemetry graphs (TX B) or the amsat website, after repeated requests here and elsewhere I'll assume it is being held secret for some reason.
There has been a tremendous lack of technical reporting on ECHO.
I realize people are very busy but time should be taken to educate the amsat community.
73, patrick N2OEQ 32323
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
Thats precisely the attitude I was alluding to. How about making the telemetry 1200 baud. Cant keep throwing money at this aspect of the hobby! Why cant you publish the information? pat On Fri, 25 Aug 2006, Andrew Glasbrenner wrote:
How about copying the telemetry yourself instead of asking someone else to do it for you. It's there whenever the digital transmitter is, and you can download software for free to decode it.
73, Drew KO4MA
----- Original Message ----- From: "McGrane" [email protected] To: "Amsat BB" [email protected] Sent: Friday, August 25, 2006 9:27 AM Subject: [amsat-bb] ECHO
greetings
I would like to report very poor reception of echo even with an 8 element yagi and an 18 Db preamp. I assume the downlink power is real flea power for battery charging or other testing.
After 2 years of pleading with amsat, the downlink power is still a mystery. It is not shown on the colaradosatellite telemetry graphs (TX B) or the amsat website, after repeated requests here and elsewhere I'll assume it is being held secret for some reason.
There has been a tremendous lack of technical reporting on ECHO.
I realize people are very busy but time should be taken to educate the amsat community.
73, patrick N2OEQ 32323
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
A very hearty thank you sir! Please find a way to post this from time to time. thank you, pat
On Fri, 25 Aug 2006, Andrew Glasbrenner wrote:
Just copied last AO-51 pass.
TXa is .3 watts TXb is .4 watts tx current draw is 800 mA panel output is 15.1 v, 1193.9 mA telemetry broadcast rate is every 10 seconds
All right there in the open for every one who wants to expend a little bit of effort to find.
73, Drew KO4MA
----- Original Message ----- From: "McGrane" [email protected] To: "Amsat BB" [email protected] Sent: Friday, August 25, 2006 9:27 AM Subject: [amsat-bb] ECHO
greetings
I would like to report very poor reception of echo even with an 8 element yagi and an 18 Db preamp. I assume the downlink power is real flea power for battery charging or other testing.
After 2 years of pleading with amsat, the downlink power is still a mystery. It is not shown on the colaradosatellite telemetry graphs (TX B) or the amsat website, after repeated requests here and elsewhere I'll assume it is being held secret for some reason.
There has been a tremendous lack of technical reporting on ECHO.
I realize people are very busy but time should be taken to educate the amsat community.
73, patrick N2OEQ 32323
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
Hi Patrick:
I work solely wit an HT, a Kenwood TH-D7AG nowadays, and either an Arrow antenna or an Elk antenna, no pre-amp whatsoever. I have no complaints about the reception of AO-51. I hear it loud and clear and I have had long distance contacts, all the way to the west coast, Guadeloupe, Venezuela and yet unconfirmed ones to Mexico and Guatemala and many shorter distance ones. To me this may suggest that the problem is not in the downlink power from Echo but somewhere on your side.
If anything, I found out lately that I now can work lower passes than I ever was able to. This seems to match the date when I started working the Kenwood TH-D7AG which I believe is more sensitive on Rx than the Yaesu VX-7 that I used before. I've worked passes at 7 degrees now whereas before 12 degrees was the best I could do from not from my QTH, but hoofing it as high as I could uphill. Canopy is still up so that is not a factor yet.
And I do live in the country so I may be lucky there according to Pat's post.
McGrane wrote:
greetings
I would like to report very poor reception of echo even with an 8 element yagi and an 18 Db preamp. I assume the downlink power is real flea power for battery charging or other testing.
73, patrick N2OEQ 32323
Thats precisely the attitude I was alluding to. How about making the telemetry 1200 baud. Cant keep throwing money at this aspect of the hobby! Why cant you publish the information? pat
The satellite is INCAPABLE of transmitting 1200 baud. There is FREE software out there that can replace a 9600 baud TNC. I like driving fast but I don't whine that I can't afford a Porsche. I barely have time to do what I've already volunteered to do and still work enough to pay my bills. You need to remember that this is a hobby for ALL of us, you included. So excuse me and the other VOLUNTEERS if we don't have the time to sit and copy telemetry and publish it for your enjoyment 24 hours of the day when you can do it yourself FOR FREE.
73, Drew KO4MA
Just copied last AO-51 pass. TXa is .3 watts TXb is .4 watts tx current draw is 800 mA panel output is 15.1 v, 1193.9 mA
I wonder what all is included in TX current, since even if the bus is an 8 volt bus, that is over 6.5 watts of DC power to produce only .7 Watts of RF or about 10% efficient? But I am sure this is not the whole story. So I shouldn't speculate...
The Hamtronics transmitters in PCSAT's draw about 500 mA to produce 2 Watts from the 12 volt bus and this is about 33% efficiency.. I think some of the HELAPS designs produce much higher efficiencies... Bob
Patrick,
Have you checked out http://www.coloradosatellite.net/echo/graph.php ?
73 Bobby - KF4GTA EM80 http://www.bobbylacey.com/KF4GTA
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of McGrane Sent: Friday, August 25, 2006 11:49 AM To: Andrew Glasbrenner Cc: [email protected] Subject: [amsat-bb] Re: ECHO
Thats precisely the attitude I was alluding to. How about making the telemetry 1200 baud. Cant keep throwing money at this aspect of the hobby! Why cant you publish the information? pat On Fri, 25 Aug 2006, Andrew Glasbrenner wrote:
How about copying the telemetry yourself instead of asking someone
else to
do it for you. It's there whenever the digital transmitter is, and you
can
download software for free to decode it.
73, Drew KO4MA
----- Original Message ----- From: "McGrane" [email protected] To: "Amsat BB" [email protected] Sent: Friday, August 25, 2006 9:27 AM Subject: [amsat-bb] ECHO
greetings
I would like to report very poor reception of echo even with an 8
element
yagi and an 18 Db preamp. I assume the downlink power is real flea
power
for battery charging or other testing.
After 2 years of pleading with amsat, the downlink power is still a mystery. It is not shown on the colaradosatellite telemetry graphs
(TX B)
or the amsat website, after repeated requests here and elsewhere
I'll
assume it is being held secret for some reason.
There has been a tremendous lack of technical reporting on ECHO.
I realize people are very busy but time should be taken to educate
the
amsat community.
73, patrick N2OEQ 32323
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
Perhaps the TLM data could be dropped into a central database such how APRS data is into APRS-IS/findu. This could give fancy reporting and alert command stations that aren't near their stations to perhaps look at the next pass of TLM, etc if there is an issue. Just an idea.
73 de Pat --- KA9SCF Amsat #35741
On 8/25/06, Andrew Glasbrenner [email protected] wrote:
How about copying the telemetry yourself instead of asking someone else to do it for you. It's there whenever the digital transmitter is, and you can download software for free to decode it.
73, Drew KO4MA
Nice chart that clearly shows the status of Echo and the fact that the output power has remained under .5 watts for an extended period of time...I've added it to my bookmarks!
Thanks Bobby!
Roger WA1KAT
----- Original Message ----- From: "Bobby Lacey" [email protected] To: [email protected] Sent: Friday, August 25, 2006 2:01 PM Subject: [amsat-bb] Re: ECHO
Patrick,
Have you checked out http://www.coloradosatellite.net/echo/graph.php ?
73 Bobby - KF4GTA EM80 http://www.bobbylacey.com/KF4GTA
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of McGrane Sent: Friday, August 25, 2006 11:49 AM To: Andrew Glasbrenner Cc: [email protected] Subject: [amsat-bb] Re: ECHO
Thats precisely the attitude I was alluding to. How about making the telemetry 1200 baud. Cant keep throwing money at this aspect of the hobby! Why cant you publish the information? pat On Fri, 25 Aug 2006, Andrew Glasbrenner wrote:
How about copying the telemetry yourself instead of asking someone
else to
do it for you. It's there whenever the digital transmitter is, and you
can
download software for free to decode it.
73, Drew KO4MA
----- Original Message ----- From: "McGrane" [email protected] To: "Amsat BB" [email protected] Sent: Friday, August 25, 2006 9:27 AM Subject: [amsat-bb] ECHO
greetings
I would like to report very poor reception of echo even with an 8
element
yagi and an 18 Db preamp. I assume the downlink power is real flea
power
for battery charging or other testing.
After 2 years of pleading with amsat, the downlink power is still a mystery. It is not shown on the colaradosatellite telemetry graphs
(TX B)
or the amsat website, after repeated requests here and elsewhere
I'll
assume it is being held secret for some reason.
There has been a tremendous lack of technical reporting on ECHO.
I realize people are very busy but time should be taken to educate
the
amsat community.
73, patrick N2OEQ 32323
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
Perhaps the TLM data could be dropped into a central database such how APRS data is into APRS-IS/findu. This could give fancy reporting and alert command stations that aren't near their stations to perhaps look at the next pass of TLM, etc if there is an issue. Just an idea. 73 de Pat --- KA9SCF
Yes, problem is that all the people who write code for ECHO are up to their necks in other work and there is not enough time to do these nice things. But yes, any satellite can trivially have a global automatic web page for telemetry and all the satellite has to do is downlink a packet in APRS telemetry format of
SATNAME>APRS:T#SSS,111,222,333,444,555,010101010
And that will turn into a historical graph up to the minute of display parameters. The FINDU web page already has a full display generator for ANY such APRS telemety packet for any station for any application. Nothing on the ground has to be done. Here are two examples:
PCSAT2 LIVE DATA:
http://www.findu.com/cgi-bin/pcsat-tele2.cgi
And for an example of a quick demo, here is a KPC-3+ in a box With a solar panel on it and its 5 channels of analog telemetry Dunked in the water as a simulated ocean buoy:
http://www.findu.com/cgi-bin/tele2.cgi?call=usna-1
And you can see where the buoy is of course by this web page:
Etc... WB4APR, Bob
Just reading the mail and wondering how the signal compares to the beacon just after launch of AO-51? I was able to copy it fine with a 1/4 2m WL mag-mount whip on a square of sheet tin. I did find that the use of a 440 MHz preamp help a whole lot!
I am asking since my tracking satellite array will not be set back up at our new QTH till next spring. In the interim I was going with the 1/4 WL whip+preamp for UHF and a turnsile for VHF.
Interested in comments.
73's Ed - KL7UW
At 10:58 AM 8/25/2006 -0400, Andrew Glasbrenner wrote:
How about copying the telemetry yourself instead of asking someone else to do it for you. It's there whenever the digital transmitter is, and you can download software for free to decode it.
73, Drew KO4MA
----- Original Message ----- From: "McGrane" [email protected] To: "Amsat BB" [email protected] Sent: Friday, August 25, 2006 9:27 AM Subject: [amsat-bb] ECHO
greetings
I would like to report very poor reception of echo even with an 8 element yagi and an 18 Db preamp. I assume the downlink power is real flea power for battery charging or other testing.
After 2 years of pleading with amsat, the downlink power is still a mystery. It is not shown on the colaradosatellite telemetry graphs (TX B) or the amsat website, after repeated requests here and elsewhere I'll assume it is being held secret for some reason.
There has been a tremendous lack of technical reporting on ECHO.
I realize people are very busy but time should be taken to educate the amsat community.
73, patrick N2OEQ 32323
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
Patrick, May I take some of your time to educate you on the reception of AO-51. First I will address your comments. The supposed flea power from my understanding is to ensure the batteries on board AO-51 remain charged to optimal conditions to achieve longevity. The downlink power is not a mystery as it is embodied in the telemetry. If you are unable to copy the telemetry, all you need to do is politely enquire on the amsat-bb. The power levels change rarely, except for special events, tests, whatever. I believe AO-51 has been published technically to a high standard. There is a huge amount of information on the Amsat-NA web-site. Do own a copy of Gould Smith's excellent publication? Now to reception of AO-51. Personally I have been monitoring AO-51 since launch, downloading and analysing telemetry, which is my particular "focus". There are many orbits I could also "shout from the rooftop" as being very poor reception. However over time I have built a profile for reception at this QTH. I know those passes that will provide excellent copy and those that leave much to be desired, albeit I operate a fully automated station. What are some of the influencing factors.
Foliage is a very well documented attenuator of 70cm signals. Australian Eucalypts to my west attest to that.
Polarisation changes occur as AO-51'a attitude varies (below). Although AO-51 is circularly polarised, there will be occasions that Vertical or Horizontal polarisation is strongly evident by the observer. This is important to users of dedicated vertical or horizontal antennae.
Because AO-51's attitude is magnetically stabilised using passive magnets, there will be occasions when the antennae are not earth pointing, hence you may experience shielding of the antennae. Theoretically the northern hemisphere is least affected, but there will be occasions when the magnitude of the earth's magnetic field may give it an extra kick and degrade performance for that particular orbit. Surprising what you can observe by just listening. Signal strength, rate & depth of QSB, signal reports being given by other users.
You state you have an 8 element yagi with a preamplifier. Is the preamp located at the antenna feed point?. If not, it should be for optimal performance. This is the most significant way to improve station performance.
Is the antenna auto tracking in az & el? If so, is it tracking correctly? High winds moved the rotator on its mount (personal experience).
Whatever your station setup, I strongly recommend that you build up a reception performance profile, over a substantive number of passes. Forget about the TX, just listen with the objective of reception improvement. By recording strength of signal, pass elevation, whether east or west, local QRM, magnitude of QSB, foliage present etc. you will quickly establish what are your optimal passes, those not optimal. I monitor many satellites. They all have strengths, weaknesses and peculiarities relative to my QTH. If we always had "arm-chair" copy the fun and challenges would quickly dissipate. There is always room for improvement, especially reception performance. 73. Colin VK5HI.
-----Original Message----- From: [email protected] [mailto:[email protected]]On Behalf Of McGrane Sent: Friday, 25 August 2006 22:57 To: Amsat BB Subject: [amsat-bb] ECHO
greetings
I would like to report very poor reception of echo even with an 8 element yagi and an 18 Db preamp. I assume the downlink power is real flea power for battery charging or other testing.
After 2 years of pleading with amsat, the downlink power is still a mystery. It is not shown on the colaradosatellite telemetry graphs (TX B) or the amsat website, after repeated requests here and elsewhere I'll assume it is being held secret for some reason.
There has been a tremendous lack of technical reporting on ECHO.
I realize people are very busy but time should be taken to educate the amsat community.
73, patrick N2OEQ 32323
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 would like to ECHO the frustration of Patrick in copying the downlink signal of AO-51 (no pun intended). Setup here is tracking EL-AZ M2 436CP30 antenna (albiet RHCP which may account for some of the difficulties). So far I have ONE PASS that I was able to copy a single ring of the beacon. Maybe a preamp is in order, but sure would be nice to get a consistent DCD on each pass. My array is well aligned as I have logged probably 50 to 60 contacts on AO-40 L-S. I have tried switching the 436CP30 over to LHCP but, sadly, corrosion on the allen screws has so far prevented such. Anyone else trying to copy telemetry with RHCP? Thanks. Jim N6FO
McGrane wrote:
greetings
I would like to report very poor reception of echo even with an 8 element yagi and an 18 Db preamp. I assume the downlink power is real flea power for battery charging or other testing.
After 2 years of pleading with amsat, the downlink power is still a mystery. It is not shown on the colaradosatellite telemetry graphs (TX B) or the amsat website, after repeated requests here and elsewhere I'll assume it is being held secret for some reason.
There has been a tremendous lack of technical reporting on ECHO.
I realize people are very busy but time should be taken to educate the amsat community.
73, patrick N2OEQ 32323
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
Hi all,
I'll be on holiday on Texel island from september 4-8th. I'll try to work some satellites with my portable station. I will use a FT817 for the uplink and an IC-R20 for the downlink. Antenne is an Arrow.
This will be my first portable sat operation so I hope I wil manage some QSOs, weather and operator dexterity permitting. Locator will be JO23.
I'm glad AO-51 is in high power mode next week, should be no problem working it.
73,
Andre PH7AT amsat 36268
participants (11)
-
Amir Findling -
Andre PH7AT -
Andrew Glasbrenner -
Bobby Lacey -
Colin Hurst -
Edward R. Cole -
James Cottle -
McGrane -
Patrick Green -
Robert Bruninga -
Roger Kolakowski