AO-85 and AnyTone TERMN-8R, full-duplex - report (long)
Hi!
After previously trying a couple of Wouxun dual-band HTs with AO-85 in the past few weeks (KG-UV8D, KG-UV9D) on AO-85, I went back to a radio I briefly tested before the AMSAT Symposium last month: the AnyTone TERMN-8R 2m/70cm FM HT. I didn't have much time to try it out then, but I gave it a try this afternoon on a 48-degree AO-85 pass over the west coast. I used the same settings in it that I did with the Wouxun KG-UV9D I tested last weekend, so I could have a baseline to compare this radio against. I was not surprised with the results.
The TERMN-8R was briefly on the market in the US earlier this year. This HT was marketed as the first HT that was certified for use in 3 different FCC- regulated services (commercial two-way radio governed by FCC Part 90, along with GMRS and MURS). Its receiver covers much more than the 2m and 70cm bands - broadcast AM and FM, shortwave (HF), and the VHF air band. The FCC revoked the TERMN-8R's certification for use in the GMRS and MURS (license- free 150 MHz VHF) services, and ordered its importer to stop selling this radio. Since amateur equipment other than RF amplifiers operating below 144 MHz sold in the US does not require FCC certification for amateur use, this radio is legal to use in this country on the 2m and 70cm ham bands by licensed radio amateurs when complying with the technical requirements in FCC Part 97.
Now that the legalities are out of the way, the simple question. Can the TERMN-8R work AO-85 full-duplex?
YES.
I worked a pass this (Thursday) afternoon around 2337 UTC. This was a pass with maximum elevation of 48 degrees, a good pass favoring the US west coast. Keeping AMSAT's recent recommendations in mind for working this satellite (low-power stations can get through on higher passes), and my own testing that appears to put the definition of "higher passes" as when AO-85 is at least 20 degrees above the horizon, I had about 7 minutes of this pass where I should have been able to get through. Using the same settings I had used with the KG-UV9D last weekend, I was able to hear the satellite well with narrow FM. I used wide FM on transmit, and I think that seems to work well with these HTs that don't have the deviation that the HTs from the traditional ham manufacturers (Icom, Kenwood, Yaesu) have.
Here are some key settings I used with the TERMN-8R, which are specific to each VFO:
Uplink VFO:
T-CDC (01): 67.0HZ STEP (10): 2.5K W/N (11): 25K TX (17): ON SQL (40): 9
Downlink VFO:
STEP (10): 2.5K W/N (11): 12.5K TX (17): OFF SQL (40): 00
As with the KG-UV8D and KG-UV9D, it does not matter which VFO is used for transmit and receive. The settings I used were with the upper (A) VFO as my transmit VFO, and the lower (B) VFO as my receive VFO. This is important for the TX menu setting, where I disabled transmitting from the receive VFO. I did not program any memory channels for use with AO-85, as the VFOs work well for this type of operation. I connected an audio splitter to the speaker jack, and fed the receive audio to an earpiece and my Sony audio recorder.
I did not try getting through AO-85 until its elevation was up to about 20 degrees. For my first transmissions as the satellite continued climbing to its maximum elevation of 48 degrees, I was hearing some noise when I transmitted that covered up the downlink. This did not last long, as I was able to hear myself while I transmitted for most of my QSOs. This HT's receiver is pretty good - a little better than the Wouxun KG-UV8D, but not as good as the Wouxun KG-UV9D. Using the 2.5 kHz tuning steps on both uplink and downlink helps a lot. More work for the operator, but the lower- power stations need all the help they can get, and some of that help is finer tuning for the uplink signals than you can do with the 5 kHz tuning steps.
I had a separate station set up in my yard to write an RF recording of this pass. I used my SDRplay SDR receiver, 8-inch Windows 10 tablet with HDSDR, and the AMSAT-UK VHF crossed dipole on an 8-foot mast and tripod. I made sure to press Record in HDSDR, so I had an RF recording. I could tell I was transmitting with a different radio, but my transmit audio was not horrible from the TERMN-8R. My transmit audio also sounded OK when I listened to the recording from my Sony audio recorder. With the occasional fades, there were times I had audio for a portion of the pass on one recording, but not the other.
I made 5 QSOs on this pass, with all 5 stations in different parts of California (KG6NUB and KB5WIA in northern California, three in southern California - K6FW, N6UK, and KB6LTY). I heard K7TRK in Oregon and N7EC north of Phoenix on as well, but I did not work these two stations. This was an orderly pass, stations leaving gaps between transmissions, which really helps for those using lower transmit power levels. Sawson KG6NUB was using around 2 watts into an Arrow Yagi and getting through for the first half of the pass I heard.
I have uploaded the MP3 recording I made from the TERMN-8R, the larger RF recording I made from HDSDR, and some photos plus a screenshot of how the pass looked from AmsatDroid Free on my mobile phone, to my Dropbox space at:
Look for the folder "20151126-AO85_Fox1A-DM43", and look for the recordings with file names containing something around 2340 UTC. Photos have file names with timestamps in local time (7 hours behind UTC), if you want to take a look at my setup before AO-85 came up from the horizon.
Since I already had the TERMN-8R, it was on my to-do list to try with AO-85. I'm glad I tried it out, since now I can say there are at least 3 Chinese-made 2m/70cm HTs that can work AO-85 full-duplex. I found that I could hear myself while transmitting to SO-50 using the TERMN-8R on very high passes, but in general it is like those Wouxun HTs I previously tried with AO-85 - don't bother trying to use it full-duplex on SO-50 or LilacSat-2 (two V/U FM satellites), without having a second radio nearby. With the TERMN-8R off the market, I wouldn't recommend trying to pick one up for working AO-85. If you want to try a Chinese-made HT with AO-85 and work this satellite full-duplex, the KG-UV9D is a better option.
73!
Patrick WD9EWK/VA7EWK http://www.wd9ewk.net/ Twitter: @WD9EWK
Another day, another awesome review by Patrick. Thank you very much for sharing this information.
Steve, W5IEM
On Thu, Nov 26, 2015, 11:06 PM Patrick STODDARD (WD9EWK/VA7EWK) < amsat-bb@wd9ewk.net> wrote:
Hi!
After previously trying a couple of Wouxun dual-band HTs with AO-85 in the past few weeks (KG-UV8D, KG-UV9D) on AO-85, I went back to a radio I briefly tested before the AMSAT Symposium last month: the AnyTone TERMN-8R 2m/70cm FM HT. I didn't have much time to try it out then, but I gave it a try this afternoon on a 48-degree AO-85 pass over the west coast. I used the same settings in it that I did with the Wouxun KG-UV9D I tested last weekend, so I could have a baseline to compare this radio against. I was not surprised with the results.
Steve,
Thanks!
Not only has it been useful to hear the recommendations from AMSAT on how to work AO-85, I think listing some radios that can do the job full-duplex is also helpful. Many older radios (most of which I don't own) should have no problems doing this on higher passes, along with some newer radios. It is much better to say "This radio can/can't work AO-85 full-duplex, and here's why... ", as opposed to making blanket statements unsupported by any testing - statements previously posted on this mailing list about some radios, and on other lists and discussion forums. With the AMSAT-BB archives open to the public, this information is being archived, and can be picked up using search engines as well.
73!
Patrick WD9EWK/VA7EWK http://www.wd9ewk.net/ Twitter: @WD9EWK
On Fri, Nov 27, 2015 at 1:01 PM, Steve May steve.w5iem@gmail.com wrote:
Another day, another awesome review by Patrick. Thank you very much for sharing this information.
Steve, W5IEM
participants (2)
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Patrick STODDARD (WD9EWK/VA7EWK)
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Steve May