> The OP required low impedance drive so adding a buffer will be necessary. If
> using LM386s then the signal from Olin's circuit would have to be attenuated
> further before feeding the LM386s.
>

Low impedance drive is not massively important - so long as it can
drive enough, then that'll do. They key goal, and the reason I used 6
LM386's in the original design, was the there could be 1, 2 3 or 6
tape recorders attached, and it's important that the amplitude is
consistant, no matter how many are connected. The easiest way to
achieve that was to keep the outputs isolated from each other.

I'm thinking that olin's circuit, driven through a pot, and into my
lm386's is going to be a good solution. I can keep the lm386's powered
up all the time and use the pic to control the op.

The only thing i'm uncertain of is how long olin's circuit will take
for the waveform to stabilise once i start outputing a square wave.
Anyone with more experience like to take a guess? or is that the sort
of thing that can be simulated?

Thanks all,

Jon
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