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Simple comparator problems. (Outputting sine wave) Answered

I just got a couple of LM2903N comparators off of an old board, and decided to do something with them.

I have it running on +/- 5V, with the (-) input on 0V, and the voltage on the (+) input varied between +/- 5V on a 100K pot.

If it is left like that, a sine wave of about 1.5V and 100Hz is generated when the (+) input is above 0V, and outputs 0V when the input is below 0V.

With the output connected to +5V via a 33K resistor, the amplitude of the sine wave is significantly reduced, to about 0.1V

Also, as the input voltage passes through 0V, the output will jump to 1.5V above or below 0V, and slowly return to 0V over about a second. The same is seen for both constant output voltage, and for the sine wave.

(Tried this with both chips, and both give the same result)

Thanks in advance for the help.


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