Could the low noise parts actually be counterfeit, relabeled as such?
Is the circuit the regulator feeds sensitive to a narrow band of voltage that the "good regulator" is outside of?
Try replacing the regulator with a battery supply and resistor divider to attain the working voltage. Move the voltage around. A good potentiometer and stiff filter capacitors are recommended so as not to introduce "pot noise".
Is something corrupting your test procedure? I had a circuit that misbehaved due to floating logic pins reacting to static electricity on the work bench. Another time a diode was photosensitive.
-- Joe Leikhim Leikhim and Associates Communications Consultants Oviedo, Florida [email protected] 407-982-0446 WWW.LEIKHIM.COM _______________________________________________ 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.
