rind mod idea

[Scott Bernardi]

I don't believe what you describe here can give you a true ring modulator,
or "balanced modulator". Every circuit I've ever seen involves the use of a
four quadrant multiplier, not just sum and difference amplifiers.

Here's a circuit that implements the multipliers with OTA's. It can also
double as a VCA with a linear CV input:

http://home.earthlink.net/~sbernardi/elec/Balmod.gif





At 04:03 PM 6/22/98 -0400, you wrote:
>Hello,
>
>I'm still recovering from that though u.s. loss yesterday.
>
>I'm new to electroinics, but I'm trying to design a ring modulator
>and have a couple questions.
>
>I have a book based on the 747 op-amp. In the book
>are small circuits for a summing amplifier and a differential amplifier.
>I was thinking that I could combine these two circuits and mix the
>outputs add a couple audio jacks and presto a genuine ring modulator,
>none of that one-input ring-mod with an internal oscillator.
>
>Now this seems almost too easy, so please tell me where I going 
>wrong...
>
>secondly, I was looking at a modulator system and saw what looked like
>a mini-patchbay that was called multiples or multiplier...
>
>could somebody explain what that is(I have a hunch) and 
>if it's simple, how to put one together.
>
>thanks in advance,
>Kristjan
>
>
>
--------------------------------------
Scott Bernardi
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scott.bernardi at fritz.com