Ok, 308 Detectives

jcpst said:
Chuck D. Bones

Post in thread 'Pandoras Box Fizzle'

LM308 test
Build this circuit on a breadboard:
LM308 pin 2 to pin 6.
pin 3 to gnd via 100K.
Pin 3 to +9V via 100K.
Pin 4 to GND.
Pin 7 thru a DMM set to measure μA to +9V.
Apply power and measure current into pin 7. Typical current draw is 300μA. I have measured as low at 250μA and as high as 360μA. Most other single opamps draw at least 1mA.

H11F1 test
Build this circuit on a breadboard:
H11F1 pin 1 to a 1K resistor.
Other side of 1K resistor thru a 5K trimpot to +9V.
H11F1 pin 2 to GND.
H11F1 pin 4 to GND.
10K resistor from H11F1 pin 6 to +9V.
Apply power and measure the...
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Have it bookmarked, thanks! I don't have any in hand yet, wanted to see if this passed the visual test first!
 
This is the way. Also, breadboard a rat and remove/replace the 30pf capacitor. Not as dispositive, but it narrows it down a lot and it's a fun circuit to breadboard.
I don't treat any silkscreen issues as dispositive of fake ICs--other than numbers that match a google image search. Or that match the numbers on the fake I got from Jameco. Which, I don't know what that actual chip is, but it's the best sounding chip I've used in a DOD250.
 
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