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Early results with Ao-40


Yesterday I was able to make some early tests with my downlink and
uplink equipment on Ao-40, and here were my results:

Downlink: My equipment included a Yaesu FT-736, an AIDC 3733
Downconverter with a Murata Filter, and a 30" x 32" offset feed Channel
Master Fiberglass dish. As recommended, I used a 75 foot run of RG-59
from my shack to the dish. I used the built-in dipole feed and reflector
that came with the downconverter.		

Uplink: In addition to the 736, I used a KLM 40 element cross yagi, with
the front third section removed, making it about a 28 element antenna. A
90 foot run of 214 sufficed for coax run to the uplink, but I had a 100
watt RF Concepts brick to provide heat if I needed it. 

Results were mostly encouraging. I found that the MB was about 120 Khz
lower than I expected, due to temperature variations and the need to
callibrate the trimmer cap on the converter. I got an S7 reading on my
downlink signals yesterday about 2200Z, with an S3 noise floor. I had
pretty good, but not exactly armchair copy of several QSOs in progress. 

On the uplink side, I got my uplink feedline rigged late, and activity
had tapered off by about 0300Z but I did make a few attempts at QSOs. I
was able to find my D/L on CW with no problems, and in fact I was
tripping LEILA at 100 watts. SSB was a bit more problematic, but I gave
it a shot and got used to the feel of tracking frequencies as doppler
shifted. I have done this a few times before with FO 20, FO 29, and
AO-10, but it has been a while. Tough hearing my downlink to track
frequencies, but I gave it a shot and called CQ a few times before I
gave up for the night. 

Listening again today, but a lot more local noise and the bird is
weaker, but seems to be improving as the pass moves along. 

73 for now, I have some more tinkering to do before things are optimal
but nonetheless I feel I am off to a good start.

Bruce N3LSY
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