Personally I'd take a few minutes to look closer at the '232 chip with the scope. Are the charge pump caps swinging 5V p-p and 10V p-p? if not swinging at all, trash the chip. Is -V pin voltage about equal to the negative of the +V pin? If so, that's OK. If not might have an output shorted, or a bad chip. Is the +V pin about +10V? If so, that's OK. If not might have an output shorted, or a bad chip. With no RS232 driving source connected does the receiver output look like a valid 5V logic high level? If not, look for a short on this line. If all these pass and the chip gets hot, replace the chip.
Bob LaJeunesse _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
