[1000mp] More info on MkV blown front end.

[Darrel Nichols]

> [Original Message]
> From: lhlousek <lhlousek@nvbell.net>
> To: 1000mp list <1000mp@mailman.qth.net>
> Date: 8/31/2003 11:10:10 PM
> Subject: [1000mp] More info on MkV blown front end.
>
> I did some troubleshooting.  There is a T/R circuit at the antenna input
to the rig that employs three transistors, a pin diode switch,  and a
relay.  The relay isn't being activated. I can make the relay work by
supplying 12V to it and the rigs receives fine.  The PNP transistor that
operates the relay is either blown or isn't getting the correct input to
switch the relay. I need to do some more signal tracing to see if I can
figure out what's going on.
>
> Lou W7HV
>


Sounds like a job for a Curve Tracer.   Found a page:

http://www.old555.com/LPE/unit/5B680B4E0BE5E522.shtml

Been using these for over 30 years and still am surprised to learn
some don't know about it.   You do need a simple scope though.

N0DBX