Hey Adioguru - whoo hoo!! ;D Finally got this circuit working!
Got new opamps and carefully replicated my wired circuit into a Visio diagram thinking it would help you, help me, find my problems... and that process pointed out a couple of mistakes I missed!
Now I think I need to work on...
Hi again, I'm sure you're right about the opamps, adioguru. Have ordered some more. Soon as I get them and replace them I'll let you know what happens. :)
Hi Audioguru, I just posted a long reply with an updated diagram but either the server hasn't had time to update it or it got lost. Having a rough night here :P. Think its time for bed.
My last comment was the suspicion of an opamp being blown which I see you have just suggested. I hope...
Hi Audioguru, yes - you're right about that diagram. I made it too quickly. But I didn't wire it according to that diagram. For building the circuit I used a printout of your diagram (its much more clear) and I made this erroneous diagram after the fact. I thought it would provide a better...
Hi Audioguru,
well I have a much cleaner looking circuit on my breadboard now. And I removed the optional 741-LED section. I have the wiper of the pot connected as you described but something is wrong somewhere :-[. So I made a pic of my circuit showing the DC voltages hoping you'll help me...
thanks for the quick response, Audioguru
I made the correction but then there was a slow steady oscillation going on that leads me to believe I made other errors. So I dismantled it and am in the process of putting it back together with a much cleaner layout. I had long leads and wires poking...
Hello Audioguru,
I'm new to this forum (and most forums) so please bear with me. I've built your circuit for the modified (corrected) stethoscope but am having problems similar to Dazza's reply #132. That being I can hear my heartbeat faintly with the pot turned down low but I can't turn it...