[sdiy] VCA troubles, NE5517

[Fredrik Carlqvist]

Hello all you brilliant people!

I am very sorry to attach the image, but I have trouble with my ISP today,
so I cannot put it on the internet. At least it is very small.

I have truble with what I thought would be a simple VCA circuit. I use half 
a NE5517. The trouble is that the control current feeds thru to the output 
in a very distinct manner. Sometimes the feedthrough is even stronger than 
the actual signal. 

Vdd is 5 volts. Vdd/2 is 2.5V. I didn't use the buffer since I 
am using a single +5V supply, and I didn't want the 1.2V drop over the 
darlington.

Can someone please help me remove the control current feedthrough?


Thanks,
Fredrik C

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