Hi Paul,
Am 20.11.2018 11:54, schrieb N1BUG:
I would like to transmit as well, but the PA is not repaired. I must
look into it to see if anything in addition to the FETs is dead,
then order FETs and whatever other parts...
When the PA is repaired I need to do some more testing before I try
WSPR-15.
Don't waste to much time, it is now the best time in the season! Do you
have a second PA, maybe a QRP version? Still worth to try!
During every WSPR-2 TX period, the scopematch shows the
resistance of the antenna decreasing during the transmission.
Maybe you can run a permanent carrier and reach negative R values then?
The world's energy problems will be finally solved! ;-)
I am
worried this is caused by something heating. Maybe the ferrite in
the antenna matching transformer, maybe the the big coil? Or maybe
it is in the scopematch detector itself but that would be a little
difficult to believe. I would like to find the cause of this before
transmitting the long WSPOR-15 periods.
Depends on how you measure the current. A saturating current transformer
will become warm or hot. Should be easy to check.
Or it is an iron dust core thermally drifting away. It is useful to
measure the voltage behind the LPF.
Just some spontan thoughts.
I just woke up and sent the rest of my overnight spots to WSPRnet:
DK7FC and DF6NM.
Nice. I see, not better than -30 dB. With WSPR-15 we are on the save side.
73, Stefan
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