aha right, ive moved the wire from pin 3 to the rail above i.e so it isnt really connected to anything. However i've still the same problem, adding a 9v battery doesnt have any effect. Infact i can unplug the opamp from the board (remove it) and theres no difference the audio signal is fed through and sounds slightly different as though its passively altered. hmmm i must have done something majorly wrong here
(ive 3 741's so hopefully i wont kill them all, and yes ive had them go up in smoke before but luckily no fire
)
(ive 3 741's so hopefully i wont kill them all, and yes ive had them go up in smoke before but luckily no fire
)ok following this:
Ive rebuilt the circuit as shown in the attached image the problem now, like ive incurred before is that theres loads of noise introduced into the circuit and the audio single is very crackly. This worsens when i power the opamp from a 9v battery. This should be simple too!
An externally hosted image should be here but it was not working when we last tested it.
Ive rebuilt the circuit as shown in the attached image the problem now, like ive incurred before is that theres loads of noise introduced into the circuit and the audio single is very crackly. This worsens when i power the opamp from a 9v battery. This should be simple too!
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DD_Davo said:
No, not connected to anything is not what clem said. Connect it to ground. Read his post again, he even drew a simple wiring didagram for you and explained it clearly. ALL your grounds are wrong.
In fact you are lucky your power amp has a DC blocking cap at the input or your would have blown up your speakers.
In future I would also recommend you breadboard with +ve at the top and -ve at the bottom to make it easier to follow. And put chips so that the pins are like 1234, not backwards. But I see you have done this now with your last pic.
yes i realised and i have done what he said but now theres the problem of introduced noise. I still cant understand the fact that powering the opamp makes no difference, i must have done something stupidly wrong since theres no amplifcation whatso ever to match the gain on the input.
Ok its de-amplyfying, by large amounts, some of the noise is from a poorly soldered 3.5mm connection so im sorting that but that unfortunately isn't going to solve the filter problem.. hmmm
Ok its de-amplyfying, by large amounts, some of the noise is from a poorly soldered 3.5mm connection so im sorting that but that unfortunately isn't going to solve the filter problem.. hmmm
Hi DD_Davo,
If you haven't solved it in 12 hours I'll see if i can put something together and take a pic of it.
Cheers!!
Clem
ps: why 12 hours - sleep time here...
Hang on - one question: when you write "...a 9V battery..." you mean TWO 9V batteries, right? If not, well, there's the problem...
If you haven't solved it in 12 hours I'll see if i can put something together and take a pic of it.
Cheers!!
Clem
ps: why 12 hours - sleep time here...
Hang on - one question: when you write "...a 9V battery..." you mean TWO 9V batteries, right? If not, well, there's the problem...
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