[amsat-bb] Midland CT890 working full duplex in AO85

Felix Paez EA4GQS ea4gqs at gmail.com
Mon Dec 28 23:08:32 UTC 2015

Hi all,

finally I have been able to do the test with AO85.

As Patrick WD9EWK/VA7EWK told me in a previous thread, It seems impossible
to work SO-50 full duplex with a single HT like this because It gets
completely saturated but today my experience with AO85 has been completely

Just at the beginning of the pass, when the satellite was still in the
horizon I have been able to hear my own voice on the downlink when nobody
seemed to still be using it. It has been only a pair of CQ calls. After
that I have lost the downlink (maybe because I have some buildings in the
way) and I haven't recovered it until it was in the middle of the pass. My
impression is that I haven't been able to excite the repeater again but it
is difficult to assure because the sat was too crowded.

The test has been done with the Midland CT890 and an Arrow Antenna using 4W.

I have a Wouxun KG-UV8D (lent to me with the Arrow from Antonio EA1IW) and
it seems the same HT as the Midland CT890 (at least externally is almost
identical and the menus are the sames, so I suppose the electronics are the
same in both HTs).

Anyway I will do more test with both HTs... but this could be great news,..

An important thing is that I have used a handheld microphone with

Another thing that I would like to say is that sometimes I hear very clear
voices when I am in 145.975 and sometimes when I am in 145.980 (in the same
pass) and it does not seem directly related to doppler. This is my

Well that is my experience of this night. Still no QSOs in this sat but I
think I am in the right way... SO-50 is not challenge anymore (each pass I
am able to do between 1 and 4 QSOs) but this tricky sat still is to me! :)

Thanks all,

Felix Paez EA4GQS

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