Hi guys,
Im having a prob. with my old timed circuit. I've designed a PCB from Bill Marsden's sch. here http://forum.allaboutcircuits.com/showpost.php?p=281377&postcount=26 . It seams like cap. Ct is not discharging I think. The circuit runs its course (6 mins.)the green led is on at start then at the end the red led and piezo turns on, But when I try to run timer again the red led and piezo turn on again instead of the green led as it should. When I short across Ct it works again. Attached is pix of PCB & Components. HELP Please. Thanks JIM
Im having a prob. with my old timed circuit. I've designed a PCB from Bill Marsden's sch. here http://forum.allaboutcircuits.com/showpost.php?p=281377&postcount=26 . It seams like cap. Ct is not discharging I think. The circuit runs its course (6 mins.)the green led is on at start then at the end the red led and piezo turns on, But when I try to run timer again the red led and piezo turn on again instead of the green led as it should. When I short across Ct it works again. Attached is pix of PCB & Components. HELP Please. Thanks JIM
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