I have found this shematics .
For R6 and R7 i have put 33kohm resisitors and i get 2.5 Volt output when there is no signal.
Anyone knows calculation for this circuit?
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I have found this shematics .
For R6 and R7 i have put 33kohm resisitors and i get 2.5 Volt output when there is no signal.
Anyone knows calculation for this circuit?
What you want is when there is no input, the output is zero.
The 1st amp is an inverting amp. so then there is no input, the - input is pulled high, making the output low.
I would increase R4 to give the inverting buffer (1st amp) a very high gain. Make R4 1Meg and see the result.
R6 and R7 are ok at 33k or 100k since they are just a voltage divider.
Larry