MOTM

That's a VCA, but there is a VCO with a GATE input:

http://www.emulatorarchive.com/AM/AM20XX/AM2200/am2200.html



>maybe that ?
>
>http://www.emulatorarchive.com/AM/AM20XX/AM2000/am2000.html
>
>  >
>>>  I have never heard of a modular VCO that stops oscillating when a CV
>>  is
>>>  absent (but then, what do I know anyway?).
>>
>>
>>    EMU vco's could function as gated oscillators. It's stalled until it
>>  receives a gate, and when the gate is removed the output continues
>>  until the waveform completes it's cycle. I don't know of any
>>  manufacturers offering this feature in a VCO today.
>>    When I was building VCO's awhile ago I experimented with implementing
>>  a gate function, but with no success. I probably just need to try
>>  harder. Any info on this subject would be greatly appreciated. Feel
>  > free to email me privately.
>>