[amsat-bb] Mobiling on AO-51

["Edward R. Cole" <al7eb@xxxxxxxxxxxxx>]

Today I drove to Anchorage (a 160-mile/3-hour trip).  I have my FT-817
mounted as a mobile with a 50w PA and dual-band whip.  I set up for AO-51
using the split-freq mode as the FT-817 is not a duplex radio on
cross-band.  In split-mode the FT-817 permits tuning one freq (Rx) while Tx
is fixed...perfect for AO-51.  One caveat is exercising extra care not to
transmit over anothers signal...since you cannot monitor the downlink when
transmitting.

I found reception on the first pass I listened, to be generally lots weaker
than my home station.  Not entirely a surprise but is was hardly
full-quieting.  The next pass was directly overhead and during the 3-min
center of the pass I was successful in making a contact with excellent
signal report.

Conclusions:  A 432 preamp would have helped.  I suspect my RF pass-thru on
the 2m-PA is lossy which really hurts reception on 435 MHz.  Solution:
bring out two connectors to break the pass-thru coax and insert 432 preamp.
I wonder if a 3/4 WL whip might have performed better than the dual-band
whip (which might not hear well in higher elevation angles).

Had it been convenient, I would have connected the FT-817 directly to the
mobile antenna for comparisons.  Comment from the other station was my 50w
was working quite well on the uplink and 5w might have been more marginal.

My next test will be using my 1/4 WL ground-plane on the 145.920 MHz uplink
and finding how low I can run power for full quieting.

73's Ed - AL7EB
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