[Elecraft] Mic Pre-Amp

[Dale Boresz]

Hello Ian,

I have used a Heil HC-5 element from the very beginning with my K2, and 
have always found that I needed to shout into it in order for it to work 
satisfactorily. However, that same microphone, a Heil HM-10, worked very 
well with my '746PRO.

In my case, I found that the levels were such that in order to overcome 
the 'knee' of the built-in noise-gate of the K2's compressor chip, I had 
to speak too loudly for comfort. If I spoke in a more normal manner, 
only the peaks would make it over the threshold.

I built the single transistor circuit of N0MF, Mike on a 1/2" x 1/2" 
circuit board, and just kind of stuffed it inside the HM-10 housing, and 
it made a big difference. I can even run the K2 with the compressor off, 
and while speaking at a normal level I still have plenty of drive, and 
have received quite a few unsolicited positive comments about the audio.

I'd highly recommend you try out the circuit. I think you'll be very 
pleased with the results.

73, Dale WA8SRA

Ian J Maude wrote:

>Hi all,
>I am currently using my K2 with a Heil HC-5 insert to good effect on
>DX.  I was wondering though if I should build a little pre-amp for the
>mic?  I notice there is a circuit on the website and I wondered if I
>would gain anything from building it?  I don't want to put too much into
>the K2 from the mic, I would just like to up the audio a little.
>
>Your thoughts appreciated.
>
>72/73
>
>Ian
>  
>