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Primer for finding your signal on AO-40

Hope this will help someone....

How to tune your radio to work AO-40

A piece of this is specific to the Yaesu 736R but the rest is general for 

There were a couple of guys on the IRC that had Yaesu 736R radios that 
were having trouble tuning it for AO-40. They could not find their downlink 
signal easily and once they did, they were drifting away.

The transponders are "inverting". This means TX on LSB and RX on USB. 
There have been some ops that are confused with this and are using USB on 
the RX and LSB on the TX. Not that you can't do it but the standard is TX on 
LSB and RX on USB. Here again, operating experience.

In a nutshell here are the steps...
1. Find the beacon on your downlink (If you can't hear the beacon, you will 
never hear your downlink, no reason to go further. The beacon is on all the 
2. Calculate where the uplink would be for the beacon (don't transmit, only 
3. Set your uplink to this calculated frequency
4. Lock your VFO's in reverse tracking 
   (ie. when you turn the dial TX goes up, RX goes down)
5. Tune up in the band past where you hear any QSO's so you don't disturb 
6. Unlock your VFO's (turn of reverse tracking)
7. Start transmitting (voice is fine, use "TEST, TEST, YOUR CALL", CW is 
okay too.)
8. Tune the receive VFO slowly up and down from where you are right now
9. You should find your uplink in a matter of seconds if you calculated the 
   starting point correctly.
10. Once you have found yourself, lock the VFO's in reverse tracking
11. Tune until you find someone you would like to have a QSO with,
    VFO's will stay together 
12. Once on the other person's frequency, unlock the VFO's
13. Adjust only the downlink, receive frequency while making the QSO. 
    (This is because he might drift up or down a little and you might drift. If you 
    both were to keep tuning the TX, you would be walking all over the band       
    trying to keep up with each other. Doppler affects the higher of the two         
    frequencies the most so the 2.4G frequency would be what you are               
  correcting for. To truly correct for doppler you should tune both RX and TX,    
 but that is another lesson which is more difficult to go into than the basic     
operating procedures here.)
14. Ready for another QSO? Go back to #10 and continue on.

Now, for those with the Yaesu 736R.
I had a Yaesu 736R once upon a time and remember how it works.

In order to get your VFO's to turn after you have loaded in a saved memory 
location into them, you have to do several steps. 

This is before you can do step 3 above
1. Load your frequency pair from memory
   You now have your starting point but your VFO's will not turn (arghh)
2. Press the button VFO=MEM or it was MEM=VFO 
   Which will swap the trash in the VFO with memory
3. Your VFO will now move, but don't do it yet
4. Press Memory Write button (this will save the value now in the VFO 
   Which you swapped from memory, back into the memory location. If you 
don't do this, you will have trash in the memory location.
5. Now, you continue with step 3 in the nutshell procedures.

Bruce Paige, KK5DO                    Internet: kk5do@arrl.net 
Houston, Texas                                  kk5do@amsat.org 
AMSAT Awards Manager                            kk5do@amsatnet.com
ARRL Awards Manager (WAS, 5BWAS, VUCC), VE                     
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