[sdiy] XR2206 as ring modulator

[anthony]

----- Original Message ----- 
From: "john mahoney" <jmahoney at gate.net>


>> Earlier I had asked about people doing weird things with the XR2206. One
> of
>> them that I was wondering about was using it as a ring moldulator. From
> the
>> datasheet, it looks like you could.
>
> Well, the discontinued XR2208 is a 4-quadrant multiplier chip. In synths,
> "ring" modulators are typically made from 4Q multipliers (which can also 
> be
> used as VCAs).
>
> The 2206 function generator has a VCO and a multiplier on board, but I 
> don't
> see an external signal input. Although it allows amplitude modulation (AM)
> and frequency modulation (FM) of the built-in VCO, you can't ring modulate
> an external signal.

What I was wondering was if one of the pins could be used as such an input 
in an undocumented (or simply untried) way.
There are probably better ways to abuse the XR2206. I've heard of a new 
Thomas Henry book regarding just that and I can't wait.

I have plenty of other chips that can be coaxed into ring modulator(ish) 
duty. (564 and 565 PLL's for two).

> john
>
>