At 02:01 PM 6/27/97 -0400, you wrote:
>> To make ring-modulation you must simply multiply two audio-rate signal!
>> 
>
>Remembering, of course, that multiplying two "complex" signal will most
>likely result in awful noise. Best try using a sine as one of the
>sources...and progressively move on to a garbage truck.

Most Ring Modulators also cancel the input signals, which is why they're
sometimes also called "suppressed-carrier modulators", so you would do
something like this:

rmout = (siga * sibg) - siga - sigb 


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On Fri, 27 Jun 1997, Steven Curtin wrote:
> Most Ring Modulators also cancel the input signals, which is why they're
> sometimes also called "suppressed-carrier modulators", so you would do
> something like this:
> 
> rmout = (siga * sibg) - siga - sigb 
> 

But aren't the input signals already effectively suppressed?

For example, cos(awt)*cos(bwt) = .5  * ( cos((a-b)wt) + cos((a+b)wt) ),

so there's already no strength at the input frequencies on the output.

What you're suggesting, it seems to me, would be in effect adding the
input signals back in. Or am I missing something?


Larry

--  Larry Troxler  --  lt@westnet.com  --  Patterson, NY USA  --