[Elecraft] K2 Vox Delay

[email protected] [email protected]
Fri Jun 27 19:45:01 2003


Hi All:

I'm using a Heil Proset with the HC-5 with my K2.  It seem to be driving the
K2 fine but I'm having trouble with the vox.   The delay time seems much
shorter than .4 and 1 sec.  I see there is an old mod in the archieves.  I'm
wondering if this is the recognized fix for a short vox delay?  I'm not sure
if I need more gain or a change to the balanced modulator or both?  Thanks
in advance.

Frank, W4FMS

From: "Steve Carey" <[email protected]>
To: <[email protected]>
Subject: K2 with Heil Pro Headset . . .
Date: Tue, 26 Feb 2002 17:16:50 -0000
Hi John,

I have just modified my K2 for use with the Heil Pro Headset ( HC-4 ). With
my K2, the Heil produces enough mV to drive the rig to full O/P . . . BUT
not sufficient to open the VOX without shouting. I proved this by wiring up
a new 8-pin Mic Plug with a PTT line and a Toggle switch. Once flipped into
TX mode, I could talk in a normal voice! Oh, when I added a pre-amp, the VOX
worked fine bt the speech just broke up and sounded dreadful.

Here is what to do ( recognised MOD ):
(It's ALL on the SSB board so it's easy to take it out and do it! )
Change R14 to 10K ( this will increase the gain of the speech amp and to the
VOX circuit )
Change R2 to 10K ( decreases I/P to Balance Modulator )


PSCH 0.4 and 1.0 is the VOX delay time after you stop talking 0.4 of a
second ( great ) and 1 second ( to long ! )

Mine sounds really nice on the headset, which I got to operate /Bike
Mobile!!
Steve/G4MJW