re suggestions on audio relays in article apr mala bc ca wagner mala bc ca tom wagner wizzard of old audio visual equipment nanaimo campus writes in article c r r id megatest com alung megatest com aaron lung writes in article c qsbf iek ms uky edu billq ms uky edu billy quinn writes i built a little project using the radio shack vdc relays to switch audio i got pretty bad clicks when the thing switched i was doing my question is is there a good relay relay circuit that i can use for switching audio so that there will be no noise of any kind on the audio lines are you switching high level signals or low level signals like pre amp a novel circuit i used to build was a primitive optical isolator it consists of a resistive photocell and a lamp all packaged in a tube when the lamp is off the cell is high resistance turn the lamp on and the resistance lowers i use an h f fet optoisolater to switch microphone level signals there is no click since i put a uf cap across the led distortion measurement are very low with mic level and they went up to at a db line level all i did was put the fet in series with one leg of the balanced line no hums pops just audio jumping out of silence the fet runs about million ohms with the led dark and drops to ohms with it on hey it works and works well galen watts kf yj
