Hi guys!
I've been working on my MXR Noise gate clone recently, but I found one issue and can't figure it out by myself. The Noise gate works, except that the last op amp U4.1 doesn't do his job. When the Bias A voltage is aplied, the bias voltage apears on both the pin 5 and 6 so then it doesnt do his job. When the bias voltage isn't aplied, then there is signal coming out of it. I added those improved active bias generator with 2 op amps. I tried to remove them so the bias voltage was taken from the resistor voltage divider but with no change. I would really apreciate your help. Thank you very much🙂. The first image is schematic of my circuit and the second one is original circuit.
I've been working on my MXR Noise gate clone recently, but I found one issue and can't figure it out by myself. The Noise gate works, except that the last op amp U4.1 doesn't do his job. When the Bias A voltage is aplied, the bias voltage apears on both the pin 5 and 6 so then it doesnt do his job. When the bias voltage isn't aplied, then there is signal coming out of it. I added those improved active bias generator with 2 op amps. I tried to remove them so the bias voltage was taken from the resistor voltage divider but with no change. I would really apreciate your help. Thank you very much🙂. The first image is schematic of my circuit and the second one is original circuit.
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That JFET must be drawn wrong, and I don't see how that output stage ever worked with no resistor in the NFB. I don't understand why the bias need four opamps?
Can you point to where you are getting these plans?
Can you point to where you are getting these plans?
Yeah that output stage bothers me too. Since this pedal is noise gate, I wanted to came up with lower noise solution for the bias voltage.
The schematic is from pedalpcb. I checked it with another MXR noise gate schematics that I found.
