Re: [amsat-bb] Re:Re: AO-40 Q&A (L1/L2)

[Charles Suckling <charles.suckling@xxxxxxxxxxxx>]

"I have no information about the missing 6 dB on L2. Perhaps it was never 
missing? There are no manual adjustments available for L2 sensitivity, just 
ON/OFF".

Stacey

In the past I checked carefully the difference in power levels required on 
L1 and L2 uplinks to achieve the same downlink level and there definitely 
was a very significant difference.  At times it was more than 6dB.  So 
something is certainly varying over time.

Personally I think Leila is best used to police U Band.  The tests we did 
showed very strong U Band signals would suppress the beacon level quite 
seriously, whereas L Band did not do this. Strong L Band signals do not 
have much effect on the level of U Band uplinked stations.  As you note, U 
Band stations suffer much more from other U Band stations than they do from 
L Band ones as a result of the U Band Agc.

What seems to be bugging people is that certain L-Band ops (not me as I 
have not been able to be active recently!) seem to be "getting away with 
it"  since Leila is not there to stop them.   Perhaps if stations did not 
report them as having "nice strong signals" but "you are more then 10dB 
below the beacon" then they might not be encouraged to keep doing it!

73

Charlie G3WDG 

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