[TenTec] Fwd: OmniVI logic board work

[Barry N1EU]

On Thu, Sep 29, 2011 at 2:33 PM, Glenn <wa4aos at aol.com> wrote:
> I meant to comment on the Ten Tec O6 audio you mentioned.
> I too ran a remote a pre DSPaudio line to the rear panel on one of my O6.
> I fed that into a combo preamp/amp I designed using a 6CW4 nuvistor as a pre amp stage, to drive
> a 6SN7/ 2A3 single ended amp stage... Ahhhhhh such sweet audio for listening to SSB; the wider INRAD filters helped as well.
> I simply turn up the front panel audio gain to re-gain DSP/ notch functionality.
> I ended up making a mini TR switch internally mounted so that default mode uses the DSP path and once the reed relays are
> energized, the audio was redirected to the rear panel.

Glenn, the key to success with tapping the audio pre-dsp is to add
some analog low pass filtering with a turn-over freq in the
3000-3500hz region and fairly steep roll off.  The Omni 6 is just TOO
hissy/noisy if you don't do this.

Barry N1EU