[Elecraft] SSB Improvements ?

[Baker]

On Thu, 25 Dec 2003 20:00:09 -0600, Jim Brown wrote:
>=A0On Fri, 19 Dec 2003 17:53:50 -0800, Ron D'Eau Claire wrote:
>
>>=A0Henry, if you are getting ALC action at the compression setting
>>=A0you like,
>>=A0raising the value of R14 more won't help at all.
>

>=A0All of that said, count me among those who would like another 6-10
>=A0dB
>=A0of gain in the mic preamp so that i can use my pro mics with the K2
>=A0without the bandaid of a stepup transformer or external preamp. =A0As
>=A0it
>=A0is now, I can't get enough level from my highest output dynamic mic
>=A0to
>=A0reliably trigger the VOX or get any ALC! =A0It was a real PITA
>=A0handholding the Heil hand mic in the recent Sweepstakes while
>=A0trying to
>=A0simultaneously maintain the log!
>
>=A0Jim K9YC
>
>=A0
I built a single transistor pre-amp which mounts internally on the mic
jumper plugs between the display and control board. It has a 680 ohm
resistor on it's input to match the two Yaesu mics that I use (MD-100
&=A0MH-31). It has 10dB of gain and the low end freq response is 3dB
down at 300Hz. It improves the VOX operation and signal levels.

The compressor IC limits the audio signal level into the 602 bal mod,
so unless it is not possible to get correct ALC action with a strong
whistle into the mic, I see no need for more gain after the 602 IC.

73

Stewart G3RXQ


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