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AO40 Transmit troubles



   After about 3 weeks of listening to AO40 and making all the final
  tweaks to the antenna/feed etc...  I decided I was hearing the bird
  well enough to try transmitting.  I am quite confused, as I could
  not hear myself come back down no matter what I tried.  
  I am using a Cal-amp D/C (still has the orig crystal...for now) so
  I find the beacon at approx 123.315 +/- doppler/drift.  
  With this setup, the converter should put the passband somewhere close
  to the range of 123.224 - 123.474 corresponding to 2401.225 - 2401.475

  Now, the U band uplink, as I understand, is from 435.800 - 435.550
  I also believe that the transponder IS inverting. So, tansmitting
  on 435.800 should correspond to 2401.225 or 123.224  +/- doppler and drift.
  I was trying to find myself near 123.240 or approx 2401.240 
  I thought my uplink should be 435.784 +/- doppler

  I cannot find myself at all.  I have a regular Oscar class setup for transmit
  (I am on AO-10 all the time with no problems) 44 element X yagi fiberglass
  boom, G5400, 350+ watt amp, andrews hardline to the top of the tower....
  Now, on AO-40, I was using about 10 watts out most of the time, the
  satellite range was about 48,000km.  I increased power very briefly
  up to 50 watts just to check and still could not find myself.  

  Am I missing something here?  I have had nothing but the best of luck
  with so many other satellites, I just can't figure out what I am doing
  wrong this time!!  (BTW- Yes, the 440 side is working, I still chat
  with people in town on 432 USB so I know the antenna is radiating..)

  Thanks with any help or suggestions!!
  73 de KI0KN  -James
  ki0kn@amsat.org
  
  
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