[Date Prev][Date Next][Thread Prev][Thread Next] - [Date Index][Thread Index][Author Index]

Re: U0-11 S band power and ant

>>This beacon is a useful test
>>source for those testing mode-S converters, as an alternative to OSCAR-40.

The above statement is absolutely correct.  A weak signal like UO-11 is a much
better source to fine tune your receive setup.  I have to deliberately
attenuate AO40, the beacon is too strong to do any final adjustments.
40 is ok for the initial rough tuning. The short time 11 is available is a
bummer, and the doppler on 11 requires some doing, but it is doable.
When you eventually hear UO-11, it is very simple to change either AZ or
EL, and the result will positively determine whether or not it is 11.

The fact there is no modulation is also an advantage, the level is not changing

UO-11 is certainly not for a beginner, but I use it all the time for a
final fine tune....Again, a pain to have to meet that short schedule,
but it produces good results.

>I keep seeing this statement, but, forgive me, it seems backwards.
>UO-11 is very weak, very high doppler shift, and relative to AO-40, very
>short passes.  There's no modulation to know that you've really got the
>right bird (or even ANY bird), and the signal's LHCP so you'll loose
>20-odd dB if you use your RHCP AO-40 setup.
>It would seem to me that AO-40 is a good test source for those wanting
>to practice for UO-11.
>Greg  KO6TH

Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org