I've got the following circuit which keeps the level of an audio signal fairly constant.
Due to adding a VU meter circuit and only having a dual OP-AMP to drive the meter, I have an extra OP-AMP section.
Is it possible to connect the inputs to the + and - inputs of the OP-AMP and use it to drive a meter to indicate how much the circuit is operating on the signal?
Due to adding a VU meter circuit and only having a dual OP-AMP to drive the meter, I have an extra OP-AMP section.
Is it possible to connect the inputs to the + and - inputs of the OP-AMP and use it to drive a meter to indicate how much the circuit is operating on the signal?
In other words: how much is the led lighting up during processing?
I would take the level from the rectifier (before the 1k resistor) and us the opamp noninv to drive the meter.
That's the idea, however it is a full wave bridge rectifier so would it be better to connect the + input to the + rectifier terminal and the - input to the - rectifier terminal?
I do have a meter with a 1-10 scale and a 1mA movement, however I am not sure how I'd light it as there's not enough room under the pop off meter cover for any bulbs.
Also that requires me to remove the other four meters and cut a hole in the cabinet for the meter which I am not looking forward to.
That said, is the meter really going to be of any use other than for there to be another moving needle for me to watch or can the OP-AMP section be better used for something else?
I do have a meter with a 1-10 scale and a 1mA movement, however I am not sure how I'd light it as there's not enough room under the pop off meter cover for any bulbs.
Also that requires me to remove the other four meters and cut a hole in the cabinet for the meter which I am not looking forward to.
That said, is the meter really going to be of any use other than for there to be another moving needle for me to watch or can the OP-AMP section be better used for something else?
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