We shut the PL tone off around the beginning of 2007 if I remember correctly. We found that the PL tone caused access problems when the satellite was very busy, due to competing signals blocking the receiver, and no downlink being passed to clue the operators into standing by and letting the other guy through. The PL tone also just masked non-amateur or out-of-bandplan signals on the uplink, but the signals were still there blocking the users, with little chance of being found and eliminated if we couldn't hear them.
We have a new PL mode we can try sometime that will turn the downlink on for n minutes, and switch to a nonPL'ed uplink for that time. This mode may let us run a higher power downlink, but it makes battery management problematic.
73, Drew KO4MA AMSAT-NA VP-Operations
----- Original Message ----- From: "Ollie Eisman" [email protected] To: "AMSAT-BB" [email protected] Sent: Monday, June 23, 2008 7:44 PM Subject: [amsat-bb] PL tone
Just out of curiosity, why is there currently no PL tone for AO-51 access?
73, Ollie, AJ1O _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb