Review of HTs for sat use
Do any of you recall where in the last 6 months or so there was an article by a ham who reviewed all of the current HTs, especially the cheap ones, for use for satellite communication? I know I'm not dreaming this and I'm soon to do a presentation for our local club and wanted to refer to this article and recommendations. Hopefully one of you can jog my ever fading memory. Rick, W2JAZ
Rick,
I didn't review *all* HTs that would work for satellite communication, but did talk about 4 of the Chinese-made dual-band HTs that could work AO-85 (and the other upcoming Fox-1 U/V FM satellites) full-duplex, with varying levels of success. That article appeared in the March/April 2016 issue of the AMSAT Journal. If you missed that issue, you can see my article in a PDF at:
Look in the Articles folder, and go to the last article in that folder (file name starts with "Working_AO85").
As with other HTs or low-power stations, you will find more success working higher AO-85 passes, and not necessarily trying to work those higher passes near AOS or LOS. With that in mind, I'm regularly working AO-85 full-duplex with a Wouxun KG-UV9D and Elk log periodic either in my back yard or in my driveway. I make my contacts when the satellite is up at least 20 to 25 degrees above the horizon.
Other than that, the situation with HTs and satellites is still the same as before. Only one HT in current production - Kenwood TH-D72A - will work all V/U and U/V FM satellites full-duplex. There are many older HTs that have been out of production a long time that will do that. The 4 Chinese-made HTs I mention in the article are able to work AO-85 and other U/V FM satellites full-duplex, but not the V/U satellites like SO-50 or LilacSat-2.
If you need more information beyond that article, please feel free to e-mail me directly. Good luck, and 73!
Patrick WD9EWK/VA7EWK http://www.wd9ewk.net/ Twitter: @WD9EWK
On Thu, Sep 22, 2016 at 12:55 AM, Richard Lawn rjlawn@gmail.com wrote:
Do any of you recall where in the last 6 months or so there was an article by a ham who reviewed all of the current HTs, especially the cheap ones, for use for satellite communication? I know I'm not dreaming this and I'm soon to do a presentation for our local club and wanted to refer to this article and recommendations. Hopefully one of you can jog my ever fading memory. Rick, W2JAZ
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What was the problem with the Chinese HT's working full duplex in the V/U modes. I don't recall that being mentioned in the article.
Jim/KA2RVO
On Wed, Sep 21, 2016 at 8:23 PM, Patrick STODDARD (WD9EWK/VA7EWK) < amsat-bb@wd9ewk.net> wrote:
Rick,
I didn't review *all* HTs that would work for satellite communication, but did talk about 4 of the Chinese-made dual-band HTs that could work AO-85 (and the other upcoming Fox-1 U/V FM satellites) full-duplex, with varying levels of success. That article appeared in the March/April 2016 issue of the AMSAT Journal. If you missed that issue, you can see my article in a PDF at:
Look in the Articles folder, and go to the last article in that folder (file name starts with "Working_AO85").
As with other HTs or low-power stations, you will find more success working higher AO-85 passes, and not necessarily trying to work those higher passes near AOS or LOS. With that in mind, I'm regularly working AO-85 full-duplex with a Wouxun KG-UV9D and Elk log periodic either in my back yard or in my driveway. I make my contacts when the satellite is up at least 20 to 25 degrees above the horizon.
Other than that, the situation with HTs and satellites is still the same as before. Only one HT in current production - Kenwood TH-D72A - will work all V/U and U/V FM satellites full-duplex. There are many older HTs that have been out of production a long time that will do that. The 4 Chinese-made HTs I mention in the article are able to work AO-85 and other U/V FM satellites full-duplex, but not the V/U satellites like SO-50 or LilacSat-2.
If you need more information beyond that article, please feel free to e-mail me directly. Good luck, and 73!
Patrick WD9EWK/VA7EWK http://www.wd9ewk.net/ Twitter: @WD9EWK
On Thu, Sep 22, 2016 at 12:55 AM, Richard Lawn rjlawn@gmail.com wrote:
Do any of you recall where in the last 6 months or so there was an
article
by a ham who reviewed all of the current HTs, especially the cheap ones, for use for satellite communication? I know I'm not dreaming this and I'm soon to do a presentation for our local club and wanted to refer to this article and recommendations. Hopefully one of you can jog my ever fading memory. Rick, W2JAZ
-- Sent from Gmail Mobile _______________________________________________ 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: http://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: http://www.amsat.org/mailman/listinfo/amsat-bb
Jim,
Looking over the article, I now see that I didn't elaborate on why none of these HTs were suitable for full-duplex operation on V/U FM satellites like SO-50 and LilacSat-2. It's a simple reason, unfortunately: the 2m transmitter in these radios desenses the 70cm receiver, when trying to hear the weak downlinks from our satellites. These radios are fine for full-duplex when transmitting on 2m, if the 70cm signal is much stronger than our satellite downlinks. Unfortunately, that's not what we have at this time. It doesn't matter which antenna you use with these radios, and whether or not you have diplexers connected to the HT.
Using another HT with one of the Chinese-made HTs I mention in the article would be one way to have a full-duplex station to work V/U FM satellites like our current SO-50 and (when it is active) LilacSat-2. SO-50's downlink in particular is a tough one for these radios, as the 436.795 MHz (+/-) frequency is only a few hundred kHz above the 3rd harmonic of the 145.850 MHz uplink. Many 2m/70cm FM mobile transceivers can handle this, but only TH-D72A in terms of HTs in current (for now) production.
73!
Patrick WD9EWK/VA7EWK http://www.wd9ewk.net/ Twitter: @WD9EWK
On Thu, Sep 22, 2016 at 1:46 AM, James Austin ka2rvo@gmail.com wrote:
What was the problem with the Chinese HT's working full duplex in the V/U modes. I don't recall that being mentioned in the article.
Jim/KA2RVO
participants (3)
-
James Austin -
Patrick STODDARD (WD9EWK/VA7EWK) -
Richard Lawn