I wanted to point out a small
error. In Figure 9 on page 19, there is
a 100 µF capacitor incorrectly
connected to the non-inverting (+)
input of the op-amp to ground. This
configuration is okay, but only if the
inverting input is to be used. However,
in the diagram, it shows both inverting
(-) and non-inverting (+) inputs being
used in this circuit. The 100 µF
capacitor to ground is essentially
shorting any audio to ground from the
non-inverting (+) input.
Solution: Connecting the 100 µF
capacitor on the +12V DC side
would be the correct placement.
Perhaps the author originally
I believe the schematic included
here will correct the problem.
EngineersGarage originally posted the
schematic and I didn't take time to
analyze it properly. At 3,000 Hz, the
capacitive reactance is only around
0.5 ohms, so the right channel would
have been short-circuited to ground.
Thanks for catching my senior
Tim Brown Q&A
READER FEEDBACK Continued from page 7
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