[Elecraft] Heil HC-4 with K2 . . .

[Steve Carey]

End of the saga . . .

My new HC-4 Pro Micro Headset would not trip the VOX unless I shout and I
mean SHOUT ( SSBa=3 SSBc=4 )!  I wired a PTT line from the 8-pin Mic Skt and
put the K2 into TX mode, the O/P of the Heil IS sufficient to produce full
O/P on all band speaking in a normal voice. I only changed R14 in effort to
hit the VOX harder . . . but the side product seems that on my K2, I was
able to overload the Balanced Modulator.

OK . . . the VOX is now working nicely, so Yes I have increased the value of
R2 to 10K. I would say that the Audio I/P to the NE612 is now abt the same
as it was before I upped the gain to the Speech Amp/Compressor (R14).

Anyway, the K2 is working very well with the HC-4.
My Leeson Table mic has a built-in amp/compressor and  I had to reduce the
O/P pot setting from 80% down to 20/25%.
When using the Heil MH-2, I have to go into settings and reduce the Mic
gain> SSBA to 1 or 2

I now get excellent reports on all three microphones.

Steve/G4MJW
K2 #2408



>R14 (on the SSB adapter) is at the Input to the Speech Compressor and R2 is
>between the Speech Compressor and the Balanced Modulator.
>
>Are you saying that increasing R14 to 10k drove the Speech Compressor so
>hard it was unable to maintain the proper level to the Balanced Modulator?
>
>I am curious about how sensitive that Speech Compressor is. I have read of
a
>number of ops using an outboard preamp ahead of it!
>
>There were some ops who swapped R2 and R14 a while back in order to get
more
>gain. That did raise some concerns about over-driving the Balanced
Modulator
>because of the swap reduced the value of R14 from 5.6 k to 1 k. But this is
>the first I've heard of being able to over drive the Speech Compressor by
>simply changing the value of R14 (If I understand you correctly).
>
>Ron AC7AC
>K2 # 1289