ic voltages

[rhdwave]

Quick question:
How do i know what the voltages should be onthe different pins of an opamp. Specifically in this case an lm386?

Much thanks!

[petemoore]

  Well the V+ power supply pin connected to the PS V+ should read the same as the V+ of the PS, ground, connected, is ground to pin 4 [Been a while...check the data sheet].
  The output makes a great voltage divider, splitting the V_/V- power rails, and left to itself should sit at 1/2v.
  Depends on what's connected after that, generally, without knowing what it depends on..the other Input pins of an OA should follow suit with the output, sitting at around 1/2 supply...but Generally I think a resistor is needed to bias the input...DAFT...been a while...better wait....
  What's this thing 'in'?

[rhdwave]

Thanks for the reply.  The ic is in a simple booster, but i put a switch before the input of the opamp so that i could use different capacitors.  Not sure if this is the problem, but so far i have no output.  Voltages seem to be correct on the opamp based on what you said.  I had some strangely enough distortion type output for a little while but at very low volume (it was actually a nice fuzzy distorted tone which i liked but have no idea why it was occurring).  Anyway, now there's nothing, bypass works fine and there's continuity in the whole circuit.  I'm thinking maybe soldering may have jumped a bit or something and maybe something's going to ground that shouldn't.