Analogue systems

>I guess the obvious should be mentioned - whether you're using FM or ring
>modulation, stick to sine tones for both the carrier and the modulator.

It is also important to experiment with the tuning of the two VCOs 
involved. If you are using a ring modulator, you need to try out 
different "out-of-tune" setting to obtain your desired bell tones.


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tw.  :)