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Success!



Well it took awhile, but finally getting a great signal from AO-40.

Started listening at 0930utc {0130 local} az=228, el=3.8 and absolutely
nothing.  I listened tuned and searched for a half hour.  I was kind of
wondering if the 50-foot trees 50-foot to the southwest were the problem.
Then I thought to check the battery that the preamp is using {it was down
to 9 volts}.  Switched batteries to one showing 12.5v but still nothing
heard.  Kept searching and decided to switch the computer over to ao40rcv
to see if its waterfall was better than FFTDSP.

About 1015, I began to hear a faint signal around 123.294.6 [2401.299.6] so
I tuned the radio and peaked the antenna and gradually the signal came up.
Strange as the squint had been 22.6 near AOS but was now up to 39 and the
range had increased from 16,300 to 26,600 km.  But the elevation was above
15 degrees by now.  That is the only thing that makes sense.
Interestingly, all the time I was shooting thru trees {and would continue
to throughout the pass}.

The signal peaked to S-8.5 {noise floor is S-6.5 to 7} from 1030-1050utc
and I got several good CRC's.  I clicked the save  button but not sure if
anything got saved {later I found a file called T010627@AL7EB.raw...how do
I look at it?}.  the single peaks on ao40rcv display reached to the next to
the top line.  Guess I need to study the operation of the sw.

After 1050 the signal began get harder to peak and CRC's were all bad.  I
quit at 1110utc: f=123.299.4 [2401.304.4], range 35,200 km, squint 49.5,
MA=33.4  By 1130 utc the signal had disappeared {az=222, el=19.5}; so much
for my theory about elevation angle.  I guess it has mostly to do with
squint angle.

My antenna pointing accuracy was interesting as elevation was exactly as
predicted by NOVA; azimuth appears to be 5 degrees off ccw.  I didn't
tryout the other Drake {#1}, but maybe next time.  Looks like I'm QRV for
mode-US.

Now all I have to do is get for work in two hours!  Ed
(x x)
  U

PS: for those want to know: 33inch offset metal dish, 5-turn helix feed,
Kuhne MKU-232A preamp {0.6 dBNF/35 dB gain}, 12-foot LMR-400 coax {1 dB
loss}, unmodified Drake, 50-foot RG-6, FT-847.

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