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L1 revisited

Hello All,
  well coincidences are running amok... either all the radar's on the planet have been re-tuned so as to have no effect on L band or
they have all been turned off now or something other than radar was causing L1 to warble...

 After the last notes about this subject I started catching each pass and recording a wav file when possible, since 8-21 I have
recorded 7 passes in which the satellites squint and or range was good enough to be able to hear my downlink, and have not detected
warble on any of them.

  I have also sent a sstv picture each time on L1 and on U,the picture is half black and half white to make any sparkles stand out,
U band is nearly always full of sparkles, L band is not, one or two but not many...

  I also went trolling through the archives and found a note from DB2OS...

"Command station G3RUH (James Miller) reported that commanding
AO-40 on L-band frequencies was fairly easy, thus it appears the
L-band receiver seems to be work nominally" (1)

this was after recovery and the satellite had just been reloaded and rudak was not on yet on,so if its hard to command now Stacey
something has changed.

  Personally I think that Rudak B or one of the experiments that run with Rudak is causing the warbles...
maybe there is bleedthru from rudak B onto L1 at the matrix... do the dsp modulators turn off when Rudak is not actively
transmitting? if yes could one be not turning off all the way and introducing so noise? maybe a voltage supply problem?   I would
think it would be worth while to find out what is really causing this before we make a similar mistake on the next sat...

  So what if it is Rudak causing it?... I for one would not suggest turning it off, it is needed too badly to support other
experiments on the Satellite but at the same time I do not feel that we should put our heads in the sand and not fully understand a
problem. I know the answer is out there, and I bet it is already known or suspected.

  Anyway I will continue to make the wavs and send the pictures and one day when something gets turned back on the L1 warble will be
back... maybe after the warble returns we can figure it out...

Kevin WA6FWF

p.s. I still looking for any stations to report if they hear any warble, so far it has only been reports on clean signals..

(1) http://ao40.homestead.com/Status.html

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