[amsat-bb] New Duplexer and AO-85

W3MAT . w3mat03 at gmail.com
Wed Oct 28 05:06:40 UTC 2015

I received my duplexer through UPS yesterday and just gave it try on the
03:20 UTC pass of AO-85.  It seems to be performing well, and I did make
contacts with K3NG and AD2KA.

I had, and continue to have, extreme difficulty with getting into AO-85
with just the HT's and Arrow antenna, and thought maybe it was because 2
meter receive and 435 up are 90 degrees to each other on the antenna's
boom.  I have had success working AO-85 with the Elk antenna and the Icom
2800 (transmits wide only), but *only* with the radios maximum 20 watts
output on UHF, and even then it can be very difficult.  I thought using the
duplexer, HT's with *narrow* band, and the Elk antenna may be the ticket.
I thought wrong.  This was just as bad, or as difficult, as trying to get
in with the Arrow antenna. In my opinion, AO-85 is certainly not every hand
held radio and Arrow antenna operators easy to work satellite, like posted
on a YouTube video prior to its launch.  I'm not a big fan of the U/V set
up for those of us that work hand held set ups.  First it was very
difficult to find the correct uplink frequencies in its early stages, and
now that they have been posted and corrected in radio programming, its
still difficult to know just when to switch for doppler, especially when
its almost impossible to get into in the first place.  I don't have multi
element, circular polarized antennas mounted on an azimuth/elevation rotor
connected to computer driven tracking and radio control software constantly
adjusting frequency, azimuth, and elevation, nor am I capable of
transmitting 50 watts of power on the uplink.  I use simple, low power
equipment (normally only 5 watts) capable of no more than 20 watts of power
(Icom 2800). AO-85's FM performance certainly does not compete with the
current SO-50, or the now gone AO-51 and AO-27 birds (rest their souls).

Have a good night,


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