Being neither a grid-chaser nor a ragchewer, I hesitate to get involved in this debate, but my flak jacket is on so here goes.
There is a fundamental difference between FM satellites and linear transponders: every LEO FM satellite that has been put up so far has only one channel, while linear transponders can accommodate several QSOs at the same time. Thus, for those of us operating from densely populated areas, using an FM satellite to talk with friends seems a misuse of available resources. It also creates an incentive to run excessive power in order to keep others from taking over the channel. A linear transponder is much better suited to that type of operation. Rapid-fire grid-chasing, state-chasing or DX chasing, on the other hand, can easily make 3 or 4 QSOs per minute, a more efficient use of a single-channel transponder.
That's my input. Now I'll go back to CW.
73 Ray W2RS
For those wanting to get on the linear birds and work portable I think the new Icom-705 might fit the bill. It will do both 144/430 MHZ full duplex QRP and give a spectrum display as well. Very similar to IC-9700 with a satellite mode. It looks promising. Far from the days of dual 817's.
Cal / N3CAL
-----Original Message----- From: AMSAT-BB [mailto:amsat-bb-bounces@amsat.org] On Behalf Of Ray Soifer via AMSAT-BB Sent: Friday, May 08, 2020 11:40 AM To: amsat-bb@amsat.org Subject: [amsat-bb] FM vs Linear Transponders
Being neither a grid-chaser nor a ragchewer, I hesitate to get involved in this debate, but my flak jacket is on so here goes.
There is a fundamental difference between FM satellites and linear transponders: every LEO FM satellite that has been put up so far has only one channel, while linear transponders can accommodate several QSOs at the same time. Thus, for those of us operating from densely populated areas, using an FM satellite to talk with friends seems a misuse of available resources. It also creates an incentive to run excessive power in order to keep others from taking over the channel. A linear transponder is much better suited to that type of operation. Rapid-fire grid-chasing, state-chasing or DX chasing, on the other hand, can easily make 3 or 4 QSOs per minute, a more efficient use of a single-channel transponder.
That's my input. Now I'll go back to CW.
73 Ray W2RS
_______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
It does not have full-duplex. If it did, it’d be the radio I was looking for!
73,
Paul, N8HM
On Friday, May 8, 2020, Cal Spreitzer via AMSAT-BB amsat-bb@amsat.org wrote:
For those wanting to get on the linear birds and work portable I think the new Icom-705 might fit the bill. It will do both 144/430 MHZ full duplex QRP and give a spectrum display as well. Very similar to IC-9700 with a satellite mode. It looks promising. Far from the days of dual 817's.
Cal / N3CAL
-----Original Message----- From: AMSAT-BB [mailto:amsat-bb-bounces@amsat.org] On Behalf Of Ray Soifer via AMSAT-BB Sent: Friday, May 08, 2020 11:40 AM To: amsat-bb@amsat.org Subject: [amsat-bb] FM vs Linear Transponders
Being neither a grid-chaser nor a ragchewer, I hesitate to get involved in this debate, but my flak jacket is on so here goes.
There is a fundamental difference between FM satellites and linear transponders: every LEO FM satellite that has been put up so far has only one channel, while linear transponders can accommodate several QSOs at the same time. Thus, for those of us operating from densely populated areas, using an FM satellite to talk with friends seems a misuse of available resources. It also creates an incentive to run excessive power in order to keep others from taking over the channel. A linear transponder is much better suited to that type of operation. Rapid-fire grid-chasing, state-chasing or DX chasing, on the other hand, can easily make 3 or 4 QSOs per minute, a more efficient use of a single-channel transponder.
That's my input. Now I'll go back to CW.
73 Ray W2RS
Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
Paul,
That's why I bought a TH-D72 rather than the TH--D74. I don't know why they took full duplex out of the D74. 73 Ray
-----Original Message----- From: Paul Stoetzer n8hm@arrl.net To: Cal Spreitzer n3cal@md.metrocast.net Cc: Ray Soifer rsoifer1@aol.com; amsat-bb@amsat.org amsat-bb@amsat.org Sent: Fri, May 8, 2020 1:03 pm Subject: Re: [amsat-bb] FM vs Linear Transponders
It does not have full-duplex. If it did, it’d be the radio I was looking for! 73, Paul, N8HM
On Friday, May 8, 2020, Cal Spreitzer via AMSAT-BB amsat-bb@amsat.org wrote:
For those wanting to get on the linear birds and work portable I think the new Icom-705 might fit the bill. It will do both 144/430 MHZ full duplex QRP and give a spectrum display as well. Very similar to IC-9700 with a satellite mode. It looks promising. Far from the days of dual 817's.
Cal / N3CAL
-----Original Message----- From: AMSAT-BB [mailto:amsat-bb-bounces@ amsat.org] On Behalf Of Ray Soifer via AMSAT-BB Sent: Friday, May 08, 2020 11:40 AM To: amsat-bb@amsat.org Subject: [amsat-bb] FM vs Linear Transponders
Being neither a grid-chaser nor a ragchewer, I hesitate to get involved in this debate, but my flak jacket is on so here goes.
There is a fundamental difference between FM satellites and linear transponders: every LEO FM satellite that has been put up so far has only one channel, while linear transponders can accommodate several QSOs at the same time. Thus, for those of us operating from densely populated areas, using an FM satellite to talk with friends seems a misuse of available resources. It also creates an incentive to run excessive power in order to keep others from taking over the channel. A linear transponder is much better suited to that type of operation. Rapid-fire grid-chasing, state-chasing or DX chasing, on the other hand, can easily make 3 or 4 QSOs per minute, a more efficient use of a single-channel transponder.
That's my input. Now I'll go back to CW.
73 Ray W2RS
______________________________ _________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/ listinfo/amsat-bb
______________________________ _________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/ listinfo/amsat-bb
participants (3)
-
Cal Spreitzer -
Paul Stoetzer -
Ray Soifer