Half-duplex on the Kenwood TH-F6A
Someone earlier was asking about the TH-F6A.
As mater of terminology, is it called "half-duplex" or "cross-band split"?
The Kenwood TH-F6A has two receivers but will not work full duplex; you cannot hear your own signal coming back down from the satellite.
What I do is use dual mode, so that both A & B are on, with the uplink on one and the downlink on the other. Set the audio fully on the downlink (because you don't want to listen to the uplink frequency) but leave the active or primary on the uplink side. That way, you can hear the bird, and when you key the PTT hopefully you can hit the bird. With an HT!
My experiences though are with the FM easysats (including AO-51 of happy memory). Has anyone had any luck with this radio's SSB receivers for the linear birds?
73,
Bob Kovacs. KC2WYH Amsat No. 38304.
Yes. Patrick, WD9EWK, has some experience using the TH-F6A as a downlink receiver. I made one QSO on VO-52 with a TH-F6A, FT-817, and Arrow antenna. I haven't gotten out to work the satellites in a while. I need to get back there,
Hear is audio of my QSO with NS1Z on VO-52 back on 10/22/12.
https://soundcloud.com/paul-stoetzer/vo-52-10-22-12
73,
Paul, N8HM
On Tue, Apr 16, 2013 at 4:20 PM, Robert Kovacs < [email protected]> wrote:
Someone earlier was asking about the TH-F6A.
As mater of terminology, is it called "half-duplex" or "cross-band split"?
The Kenwood TH-F6A has two receivers but will not work full duplex; you cannot hear your own signal coming back down from the satellite.
What I do is use dual mode, so that both A & B are on, with the uplink on one and the downlink on the other. Set the audio fully on the downlink (because you don't want to listen to the uplink frequency) but leave the active or primary on the uplink side. That way, you can hear the bird, and when you key the PTT hopefully you can hit the bird. With an HT!
My experiences though are with the FM easysats (including AO-51 of happy memory). Has anyone had any luck with this radio's SSB receivers for the linear birds?
73,
Bob Kovacs. KC2WYH Amsat No. 38304.
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
Robert,
My experiences though are with the FM easysats (including AO-51 of happy memory). Has anyone had any luck with this radio's SSB receivers for the linear birds?
I have a TH-F6A, and have used it as the downlink receiver when working SSB via satellite. I use an FT-817ND as my uplink transmitter, and will occasionally use the TH-F6A as the downlink receiver in place of another FT-817ND. The all-mode receiver in the TH-F6A is not as sensitive nor as selective as the receiver in the FT-817ND for SSB and CW, but it can work. I don't work the lowest passes on VO-52 with the TH-F6A as my receiver, and only look at the higher passes for FO-29 - but it can work this way.
I have recently purchased the 2m/70cm broadband preamp from AMSAT, but have not had a chance to try it out. As long as I don't swamp the front end of the TH-F6A's receiver, that HT with the preamp may be my ticket to a better receive setup with the HT. Even without the preamp, I have done demonstrations using an FT-817ND with a TH-F6A, making for a very small and portable all-mode satellite station.
73!
Patrick WD9EWK/VA7EWK http://www.wd9ewk.net/
I have had some luck using the HT's SSB mode to listen to some of the "Beepsat" beacons. This was done for educational purposes to show the effects of polarization to non-believers. Using an arrow style antenna (homebrew version) mounted on a tripod, we would dial in the CW beacon of a bird with linear polarization. After matching up polarizations by twisting the arrow to maximize the volume out of the TH-F6A we would have the "onlookers" mentally note the volume of the beacon then quickly twist the beam 90 degrees (while maintaining azimuth and elevation the same). The previously clear and strong beacon would all but disappear from the audio. We would then twist back 90 degrees and the beacons would come right back nice and strong.
The onlooking non-believers jaws would drop, eyes would widen, and learning would occur.
I have yet to try it out with the SSB voice transponders, mainly because you can't transmit SSB so there's no chance of making a QSO with just the HT.
However, the future of the Amateur Satellites is evolving and we will "soon" be seeing more software defined radio technology being incorporated into the transponders. This technology will allow previously unheard of modes of operation that could allow these types of HTs to complete a QSO. Imagine a software defined transponder that receives an uplink in FM and downlinks SSB. Piece of cake for the SDR wizards. A satellite that can do that is good news for owners of these types of HTs. As mentioned by Patrick below, these types of HTs will not match the performance of the work horse satellite radios (FT-817, FT-847, FT-857, IC-910H, etc.), but for those good high passes, with a decent antenna, I bet it will probably work.
-Zach, KJ4QLP
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Patrick STODDARD (WD9EWK/VA7EWK) Sent: Tuesday, April 16, 2013 4:41 PM To: [email protected] Subject: [amsat-bb] Re: Half-duplex on the Kenwood TH-F6A
Robert,
My experiences though are with the FM easysats (including AO-51 of happy memory). Has anyone had any luck with this radio's SSB receivers for the linear birds?
I have a TH-F6A, and have used it as the downlink receiver when working SSB via satellite. I use an FT-817ND as my uplink transmitter, and will occasionally use the TH-F6A as the downlink receiver in place of another FT-817ND. The all-mode receiver in the TH-F6A is not as sensitive nor as selective as the receiver in the FT-817ND for SSB and CW, but it can work. I don't work the lowest passes on VO-52 with the TH-F6A as my receiver, and only look at the higher passes for FO-29 - but it can work this way.
I have recently purchased the 2m/70cm broadband preamp from AMSAT, but have not had a chance to try it out. As long as I don't swamp the front end of the TH-F6A's receiver, that HT with the preamp may be my ticket to a better receive setup with the HT. Even without the preamp, I have done demonstrations using an FT-817ND with a TH-F6A, making for a very small and portable all-mode satellite station.
73!
Patrick WD9EWK/VA7EWK http://www.wd9ewk.net/ _______________________________________________ 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
participants (4)
-
Patrick STODDARD (WD9EWK/VA7EWK) -
Paul Stoetzer -
Robert Kovacs -
Zach Leffke