[CQ-Contest] MFJ-432 Voice keyer questions...troubles

Tom Delker k1ky at bellsouth.net
Mon Nov 2 11:33:26 EST 1998

KI9A at aol.com wrote:
> I have an MFJ 432 voice keyer I bought a few years ago that I am having RF
> troubles with. 

K1KY Writes:
I believe you will find that there is a critical design flaw where they
have put an inductor (L6) in the ground return of the mic circuit.  I
have two of these units and could not make them work unless running them
from an external 12 volt battery.  If I used my equipment power, all
sorts of nasty things would happen to the audio.

Simply solder a piece of wire across L6. 

If you are interested in computer interface, you can find my solutions
to that in the e-mail archives.

Let me know if this solves your problem.


Thomas M. Delker - K1KY CFO#395 - Smyrna / Gallatin / Short Mtn. TN
A.R.R.L. District Emergency Coordinator - Tennessee District #4
C.A.T.S. (W4CAT) - 147.30/145.23/145.49/145.17/223.98/444.45/444.65
Stones River A.R.C. (K4FUN) - http://www.members.home.com/srarc
Tennessee Contest Group (K4TCG) - http://www.k4ro.net/tcg.html
Fistfighters United Nashville (NT4L) 146.955 (114.8)

CQ-Contest on WWW:        http://www.contesting.com/_cq-contest/
Administrative requests:  cq-contest-REQUEST at contesting.com

More information about the CQ-Contest mailing list