As many already know the K3 AGC kicks in when the MH2 mic PTT switch is
pressed and that causes the first few words to be attenuated after keying
the mic.
Elecraft told me that was caused by the mechanical noise the PTT switch in
the mic makes and they plan to address it by and by.
Not so! The stimulation of AGC is caused by a current transient in the PTT
switch circuit that is coupled into the mic audio line in the mic cable
going to the K3.
My guess is that a filter capacitor in the K3 is being discharged by the PTT
switch and that generates a sufficiently high current spike to cause the
problem.
I just performed surgery on my mic connector to add a 150 ohm resistor in
series with pin 2 (PTT line) and that is all it took to eliminate that AGC
transient. No more lost words. It was messy surgery and not for the faint
of heart but it works.
Don K7FJ
_______________________________________________
Elecraft mailing list
Post to: [email protected]
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.htm
Elecraft web page: http://www.elecraft.com
