Richard:
I made some changes in mine. It was done in an effort to solve, what I
thought was an RF problem, but in doing so, I found that I got better
audio reports.
Change R1 from 100K to 68K. Change C4 from 220pf to 330pf.
This does reduce the gain of the mic pre-amp stage and maintains the
same frequency compensation. The result is that the input to the 1st
stage of the Omni VI+ is reduced and (it was my determination) that the
front end audio clipping was eliminated. After the modification, the
Omni mic level control must be advanced to about the 10 to 11 o'clock
position. (Normally it runs about 9 o'clock) The mic level control is
electrically located between the 1st and 2nd stages.
73
Bob K4TAX
nw4p@martha.xtn.net wrote:
>
> Gentlemen,
> Someone mentioned a mod to the 705 mic to change the audio.
> What was the mod and how is the audio affected ??
>
> Tnx Richard NW4P
>
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