Yep, been using one of those for years!
I have a Sinclair Labs unit that provides 100dB rejection outside of the 2 Meter band.
Jim KQ6EA
On 01/19/2014 07:32 PM, w4tas wrote:
I would also suggest a low pass filter on the two meter transmitter. A diplexer will work well for this also. This will reduce the third harmonic which is causing your problem.
Good luck,
-----Original Message----- From: Jim Jerzycke Sent: Sunday, January 19, 2014 2:09 PM To: amsat-bb@amsat.org Subject: [amsat-bb] Re: 145 MHz signal blocking 435 MHz downlink
Buy a diplexer, and connect it as shown in the linked article:
http://www.amsat.org/amsat-new/articles/Mode-J/
I also tilt both of my Yagis so they're 45* to the boom, which makes them 90* to each other.
Yes, I lose some signal on terrestrial use, but ti helped cut the coupling, and desense, down quite a bit.
73, Jim KQ6EA
On 01/19/2014 06:56 PM, Gabriel - EA6VQ wrote:
Hi all,
I have a coupling problem in my station when trying to work FO-29. My 2m signal is completely blocking the 435 MHz downlink, and so I can't hear my signal off the satellite. I guess it must be something related to the distance between the two yagis. (I use the terrestrial horizontal yagis you can see at http://www.dxmaps.com/jm19hn.html ). With mode-B satellites there is no problem. I have tried it with two different 435 receivers, and it's exactly the same.
Anyone has had this problem o have an idea of the possible reason? And what is more important, of some way to solve it?
Thanks for any possible help.
- Gabriel - EA6VQ
Web-Site: HTTP://www.dxmaps.com VQLog 3.1 (build 78): HTTP://www.vqlog.com _________________________________________________________
Sent via AMSAT-BB@amsat.org. 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 AMSAT-BB@amsat.org. 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 know this has been answered before, but I forget. Given one Diplexer, is it better to put it on the Tx side to limit the 3rd harmionic going out, or better on the Rx side to limit the VHF fundamental coming in? Tony's diagram shows the later; I would have thought the former would be more effective (hitting the problem at its source).
Greg KO6TH
Jim Jerzycke wrote:
Yep, been using one of those for years!
I have a Sinclair Labs unit that provides 100dB rejection outside of the 2 Meter band.
Jim KQ6EA
On 01/19/2014 07:32 PM, w4tas wrote:
I would also suggest a low pass filter on the two meter transmitter. A diplexer will work well for this also. This will reduce the third harmonic which is causing your problem.
Good luck,
-----Original Message----- From: Jim Jerzycke Sent: Sunday, January 19, 2014 2:09 PM To: amsat-bb@amsat.org Subject: [amsat-bb] Re: 145 MHz signal blocking 435 MHz downlink
Buy a diplexer, and connect it as shown in the linked article:
http://www.amsat.org/amsat-new/articles/Mode-J/
I also tilt both of my Yagis so they're 45* to the boom, which makes them 90* to each other.
Yes, I lose some signal on terrestrial use, but ti helped cut the coupling, and desense, down quite a bit.
73, Jim KQ6EA
On 01/19/2014 06:56 PM, Gabriel - EA6VQ wrote:
Hi all,
I have a coupling problem in my station when trying to work FO-29. My 2m signal is completely blocking the 435 MHz downlink, and so I can't hear my signal off the satellite. I guess it must be something related to the distance between the two yagis. (I use the terrestrial horizontal yagis you can see at http://www.dxmaps.com/jm19hn.html ). With mode-B satellites there is no problem. I have tried it with two different 435 receivers, and it's exactly the same.
Anyone has had this problem o have an idea of the possible reason? And what is more important, of some way to solve it?
Thanks for any possible help.
- Gabriel - EA6VQ
Web-Site: HTTP://www.dxmaps.com VQLog 3.1 (build 78): HTTP://www.vqlog.com _________________________________________________________
Sent via AMSAT-BB@amsat.org. 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 AMSAT-BB@amsat.org. 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 AMSAT-BB@amsat.org. 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
Since I use a very good 2 Meter bandpass filter on my 2 Meter output, I use the diplexer AT the antenna, ahead of the preamp.
Jim KQ6EA
On 01/20/2014 03:41 AM, Greg D wrote:
I know this has been answered before, but I forget. Given one Diplexer, is it better to put it on the Tx side to limit the 3rd harmionic going out, or better on the Rx side to limit the VHF fundamental coming in? Tony's diagram shows the later; I would have thought the former would be more effective (hitting the problem at its source).
Greg KO6TH
Jim Jerzycke wrote:
Yep, been using one of those for years!
I have a Sinclair Labs unit that provides 100dB rejection outside of the 2 Meter band.
Jim KQ6EA
On 01/19/2014 07:32 PM, w4tas wrote:
I would also suggest a low pass filter on the two meter transmitter. A diplexer will work well for this also. This will reduce the third harmonic which is causing your problem.
Good luck,
-----Original Message----- From: Jim Jerzycke Sent: Sunday, January 19, 2014 2:09 PM To: amsat-bb@amsat.org Subject: [amsat-bb] Re: 145 MHz signal blocking 435 MHz downlink
Buy a diplexer, and connect it as shown in the linked article:
http://www.amsat.org/amsat-new/articles/Mode-J/
I also tilt both of my Yagis so they're 45* to the boom, which makes them 90* to each other.
Yes, I lose some signal on terrestrial use, but ti helped cut the coupling, and desense, down quite a bit.
73, Jim KQ6EA
On 01/19/2014 06:56 PM, Gabriel - EA6VQ wrote:
Hi all,
I have a coupling problem in my station when trying to work FO-29. My 2m signal is completely blocking the 435 MHz downlink, and so I can't hear my signal off the satellite. I guess it must be something related to the distance between the two yagis. (I use the terrestrial horizontal yagis you can see at http://www.dxmaps.com/jm19hn.html ). With mode-B satellites there is no problem. I have tried it with two different 435 receivers, and it's exactly the same.
Anyone has had this problem o have an idea of the possible reason? And what is more important, of some way to solve it?
Thanks for any possible help.
- Gabriel - EA6VQ
Web-Site: HTTP://www.dxmaps.com VQLog 3.1 (build 78): HTTP://www.vqlog.com _________________________________________________________
Sent via AMSAT-BB@amsat.org. 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 AMSAT-BB@amsat.org. 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 AMSAT-BB@amsat.org. 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 more I read about it, the more I expect that the right answer depends on one's particular receive-side hardware. If it's already got good out of band filtering, then the hi-pass filter offered by the posted diagram won't help, since it's aimed at reducing the 2m fundamental overload. For that, you need to use the 2m port on the Tx side (Tx to Common, 2m port to antenna, leaving the 70cm port unconnected).
On the other hand, if the receiver pretty wide open, then the 2m fundamental is the main problem, and the posted receive-side design will eliminate it before it hits the receive chain.
Yes?
Greg KO6TH
Jim Jerzycke wrote:
Since I use a very good 2 Meter bandpass filter on my 2 Meter output, I use the diplexer AT the antenna, ahead of the preamp.
Jim KQ6EA
On 01/20/2014 03:41 AM, Greg D wrote:
I know this has been answered before, but I forget. Given one Diplexer, is it better to put it on the Tx side to limit the 3rd harmionic going out, or better on the Rx side to limit the VHF fundamental coming in? Tony's diagram shows the later; I would have thought the former would be more effective (hitting the problem at its source).
Greg KO6TH
Jim Jerzycke wrote:
Yep, been using one of those for years!
I have a Sinclair Labs unit that provides 100dB rejection outside of the 2 Meter band.
Jim KQ6EA
On 01/19/2014 07:32 PM, w4tas wrote:
I would also suggest a low pass filter on the two meter transmitter. A diplexer will work well for this also. This will reduce the third harmonic which is causing your problem.
Good luck,
-----Original Message----- From: Jim Jerzycke Sent: Sunday, January 19, 2014 2:09 PM To: amsat-bb@amsat.org Subject: [amsat-bb] Re: 145 MHz signal blocking 435 MHz downlink
Buy a diplexer, and connect it as shown in the linked article:
http://www.amsat.org/amsat-new/articles/Mode-J/
I also tilt both of my Yagis so they're 45* to the boom, which makes them 90* to each other.
Yes, I lose some signal on terrestrial use, but ti helped cut the coupling, and desense, down quite a bit.
73, Jim KQ6EA
On 01/19/2014 06:56 PM, Gabriel - EA6VQ wrote:
Hi all,
I have a coupling problem in my station when trying to work FO-29. My 2m signal is completely blocking the 435 MHz downlink, and so I can't hear my signal off the satellite. I guess it must be something related to the distance between the two yagis. (I use the terrestrial horizontal yagis you can see at http://www.dxmaps.com/jm19hn.html ). With mode-B satellites there is no problem. I have tried it with two different 435 receivers, and it's exactly the same.
Anyone has had this problem o have an idea of the possible reason? And what is more important, of some way to solve it?
Thanks for any possible help.
- Gabriel - EA6VQ
Web-Site: HTTP://www.dxmaps.com VQLog 3.1 (build 78): HTTP://www.vqlog.com _________________________________________________________
Sent via AMSAT-BB@amsat.org. 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 AMSAT-BB@amsat.org. 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 AMSAT-BB@amsat.org. 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
Well, from my experience, every little bit helps.....
I first had the two antennas mounted horizontally on the cross boom, and had some interference/desense. Then I installed the diplexer, and it lessened. Then I put the 2 Meter bandpass filter on the transmitter, and it improved some more. Then I mounted the two antennas at 45* to the boom, making them 90* to each other, and it went down some more.
Short of hanging huge cavity filters on the antenna, and using a 20' cross boom, I don't think there's much more I could do!
73, Jim
On 01/20/2014 04:54 AM, Greg D wrote:
The more I read about it, the more I expect that the right answer depends on one's particular receive-side hardware. If it's already got good out of band filtering, then the hi-pass filter offered by the posted diagram won't help, since it's aimed at reducing the 2m fundamental overload. For that, you need to use the 2m port on the Tx side (Tx to Common, 2m port to antenna, leaving the 70cm port unconnected).
On the other hand, if the receiver pretty wide open, then the 2m fundamental is the main problem, and the posted receive-side design will eliminate it before it hits the receive chain.
Yes?
Greg KO6TH
Jim Jerzycke wrote:
Since I use a very good 2 Meter bandpass filter on my 2 Meter output, I use the diplexer AT the antenna, ahead of the preamp.
Jim KQ6EA
On 01/20/2014 03:41 AM, Greg D wrote:
I know this has been answered before, but I forget. Given one Diplexer, is it better to put it on the Tx side to limit the 3rd harmionic going out, or better on the Rx side to limit the VHF fundamental coming in? Tony's diagram shows the later; I would have thought the former would be more effective (hitting the problem at its source).
Greg KO6TH
Jim Jerzycke wrote:
Yep, been using one of those for years!
I have a Sinclair Labs unit that provides 100dB rejection outside of the 2 Meter band.
Jim KQ6EA
On 01/19/2014 07:32 PM, w4tas wrote:
I would also suggest a low pass filter on the two meter transmitter. A diplexer will work well for this also. This will reduce the third harmonic which is causing your problem.
Good luck,
-----Original Message----- From: Jim Jerzycke Sent: Sunday, January 19, 2014 2:09 PM To: amsat-bb@amsat.org Subject: [amsat-bb] Re: 145 MHz signal blocking 435 MHz downlink
Buy a diplexer, and connect it as shown in the linked article:
http://www.amsat.org/amsat-new/articles/Mode-J/
I also tilt both of my Yagis so they're 45* to the boom, which makes them 90* to each other.
Yes, I lose some signal on terrestrial use, but ti helped cut the coupling, and desense, down quite a bit.
73, Jim KQ6EA
On 01/19/2014 06:56 PM, Gabriel - EA6VQ wrote:
Hi all,
I have a coupling problem in my station when trying to work FO-29. My 2m signal is completely blocking the 435 MHz downlink, and so I can't hear my signal off the satellite. I guess it must be something related to the distance between the two yagis. (I use the terrestrial horizontal yagis you can see at http://www.dxmaps.com/jm19hn.html ). With mode-B satellites there is no problem. I have tried it with two different 435 receivers, and it's exactly the same.
Anyone has had this problem o have an idea of the possible reason? And what is more important, of some way to solve it?
Thanks for any possible help.
- Gabriel - EA6VQ
Web-Site: HTTP://www.dxmaps.com VQLog 3.1 (build 78): HTTP://www.vqlog.com _________________________________________________________
Sent via AMSAT-BB@amsat.org. 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 AMSAT-BB@amsat.org. 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 AMSAT-BB@amsat.org. 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 AMSAT-BB@amsat.org. 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 Greg.
Most decent VHF transmitters will already have a pretty good LPF on the output to reduce the harmonics.
However, receivers these days tend to be DC-Daylight, so frequently need a filter to prevent 'blocking' by unwanted high level signals. In that case preventing the VHF coming into the UHF receiver can be important
Thanks
David
-----Original Message----- From: Greg D ko6th.greg@gmail.com To: Jim Jerzycke kq6ea@verizon.net; w4tas w4tas@gte.net; 'AMSAT Mailing List' amsat-bb@amsat.org Sent: Mon, 20 Jan 2014 3:47 Subject: [amsat-bb] Re: 145 MHz signal blocking 435 MHz downlink
I know this has been answered before, but I forget. Given one Diplexer, is it better to put it on the Tx side to limit the 3rd harmionic going out, or better on the Rx side to limit the VHF fundamental coming in? Tony's diagram shows the later; I would have thought the former would be more effective (hitting the problem at its source).
Greg KO6TH
Jim Jerzycke wrote:
Yep, been using one of those for years!
I have a Sinclair Labs unit that provides 100dB rejection outside of the 2 Meter band.
Jim KQ6EA
On 01/19/2014 07:32 PM, w4tas wrote:
I would also suggest a low pass filter on the two meter transmitter. A diplexer will work well for this also. This will reduce the third harmonic which is causing your problem.
Good luck,
-----Original Message----- From: Jim Jerzycke Sent: Sunday, January 19, 2014 2:09 PM To: amsat-bb@amsat.org Subject: [amsat-bb] Re: 145 MHz signal blocking 435 MHz downlink
Buy a diplexer, and connect it as shown in the linked article:
http://www.amsat.org/amsat-new/articles/Mode-J/
I also tilt both of my Yagis so they're 45* to the boom, which makes them 90* to each other.
Yes, I lose some signal on terrestrial use, but ti helped cut the coupling, and desense, down quite a bit.
73, Jim KQ6EA
On 01/19/2014 06:56 PM, Gabriel - EA6VQ wrote:
Hi all,
I have a coupling problem in my station when trying to work FO-29. My 2m signal is completely blocking the 435 MHz downlink, and so I can't hear my signal off the satellite. I guess it must be something related to the distance between the two yagis. (I use the terrestrial horizontal yagis you can see at http://www.dxmaps.com/jm19hn.html ). With mode-B satellites there is no problem. I have tried it with two different 435 receivers, and it's exactly the same.
Anyone has had this problem o have an idea of the possible reason? And what is more important, of some way to solve it?
Thanks for any possible help.
- Gabriel - EA6VQ
Web-Site: HTTP://www.dxmaps.com VQLog 3.1 (build 78): HTTP://www.vqlog.com _________________________________________________________
Sent via AMSAT-BB@amsat.org. 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 AMSAT-BB@amsat.org. 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 AMSAT-BB@amsat.org. 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 AMSAT-BB@amsat.org. 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
Can anyone measure the balun and phasing lines for 436cp30 and 2mcp14 and tell me the lengths? Anyone with spares available? It seems my dogs loved the flavor they had.
Easy enough to make, the problem is that the crimping tool is 40-60$ M2 charges 66 bux for all four. Still waiting for my parts. Ordered them two months ago. 73 de Norm n3ykf
On Mon, Jan 20, 2014 at 8:29 AM, Floyd Rodgers kc5qbc@swbell.net wrote:
Can anyone measure the balun and phasing lines for 436cp30 and 2mcp14 and tell me the lengths? Anyone with spares available? It seems my dogs loved the flavor they had. _______________________________________________ Sent via AMSAT-BB@amsat.org. 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
Probably not quite the quality, but I was planning to use compression fittings and tool from Home Depot since I have both. Any hints on length or the design frequency? Guess I could construct based on where I plan to use them.
That reminds me of the months I've been waiting on ball bearings for the Yaesu az/el rotor which is why the antennas were on the ground where the beasts live. Four pits actually defend them from other things pretty well, and you wouldn't believe what they can do to 7/8 hardline.
Compression fittings from home depot work. I have the baluns and phasing gear for both your antennas, as I have a set myself. The436cp30 ones are off and I can measure them directly. However the 2m antenna is on the tower. I will have that down in a few days. Will make measurements for you. Norm n3ykf
On Mon, Jan 20, 2014 at 10:38 AM, Floyd Rodgers kc5qbc@swbell.net wrote:
Probably not quite the quality, but I was planning to use compression fittings and tool from Home Depot since I have both. Any hints on length or the design frequency? Guess I could construct based on where I plan to use them.
That reminds me of the months I've been waiting on ball bearings for the Yaesu az/el rotor which is why the antennas were on the ground where the beasts live. Four pits actually defend them from other things pretty well, and you wouldn't believe what they can do to 7/8 hardline.
Sent via AMSAT-BB@amsat.org. 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
participants (5)
-
Floyd Rodgers -
g0mrf＠aol.com -
Greg D -
Jim Jerzycke -
Lizeth Norman