Posted by
Don Wilhelm-3 on
Apr 23, 2006; 1:11am
URL: http://elecraft.85.s1.nabble.com/Strange-receive-problem-tp389057p389059.html
Joe,
Try checking the RF voltage out of the VCO (at TP1) - compare 30 meters to
40 and 20. If the 30 meter output is low, that could be the major cause of
your problem. If this is the situation, look first at the voltage at R30
for clues. Normally the 30 meter VCO alignment falls quite within range,
but if the capacitors in the VFO selection area are not quite the right
value, it could make any one band go out of range.
Other than the BPF and the VFO range, there is not much that is band
specific in the receiver - all it takes is things tuned to the correct
frequencies.
73,
Don W3FPR
> -----Original Message-----
>
> I have been pulling my hair out for about a month with this
> problem, and perhaps someone has seen it before and can point me
> on the right path.
>
> I have an issue on 30m receive only. When I transmit on 30m I
> get full power, and it receives normal, but after a while it
> loses most of its sensitivity. Transmit again and it will hear
> the other side of the earth. I have noticed that once it goes
> partially deaf I can get a High Curr indication on the first dash
> I send, but after that it puts out full power with no complaints
> and of course after every transmission it is that beautiful K2 receive.
>
> Here is the kicker - 20m is great. The only difference in the
> LPF is K3 switches out some capacitors. I have resoldered all
> the connections, and replaced K3 (bought a Hakko 808 just to do it).
>
> I think we can eliminate the BPF as nothing changes in it for
> either 30 or 20. And since I replaced K3, I am beginning to give
> up hope that it is something in the LPF.
>
>
_______________________________________________
Elecraft mailing list
Post to:
[hidden email]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft
Help:
http://mailman.qth.net/subscribers.htmElecraft web page:
http://www.elecraft.com