[barqy]

hey all, my first attempt at building a DIY amp and has been somewhat unsuccessful...

Anyway, there doesn't seem to be any sound coming from my cmoy!

I'm pretty sure I have things wired correctly (volume pot etc.) as I followed this post here: http://www.head-fi.org/forums/showpo...78&postcount=5


I have no sound/volume from the amp at all, any suggestions? The +/- hookup wire is the same + 4.49/ -4.4.9 respectively.

Any suggestions? I'm sure this has been done before

but I don't really have much experience with electronics clearly...


TIA.

 

[Pars]

From you lower pic it isn't clear, but do you have your R4 resistors in? I can't tell from your pic, but it doesn't look like it. Incomplete feedback loop (which R4/R5 are part of) = no sound.

 

[barqy]

Hi,

Yes there are R4 resistors in, the input capacitors are covering it up in that pic...

 

[looser101]

Check against the info here: Cmoy

Hope everything goes well for you, and enjoy your cmoy.

Renato

 

[looser101]

double post

 

[barqy]

I'm pretty sure it's correct?

I looked up the specs on the TI website and that's how it's suppose to be oriented according to how I wired it...

The other way around makes the op amp get super hot ( i made this mistake on the first op amp I wasted)....


i made sure there was no heat coming from the op amp at all, so it should be fine...?

 

[looser101]

You are right, I double checked. I edited my post to correct it. Can you post a picture of your jacks as well.

Renato

 

[heatmizer]

Is the socket backward? Do you have another opamp. Everything looks correct can't see the jacks though

 

[looser101]

The socket is backwards. No biggie there.

 

[barqy]

Quote:

Originally Posted by looser101 /img/forum/go_quote.gif You are right, I double checked. I edited my post to correct it. Can you post a picture of your jacks as well. Renato

Jacks?

Like this pic:

thanks

 

[MisterX]

First picture, orange and white wire/ V+ rail, where it connects to pin 8 on the op-amp is about the only "problem" that jumps out at me from the images.

 

[barqy]

sorry i haven't gotten back to this thread, went on vacation for a bit.


so what's wrong w/ the orange/white wire connected to pin8? it gives me the correct voltage...

thanks in advance

 

[Pars]

I'm not sure what MisterX was referring to as it looks OK to me. If you test with your DMM, do you get +/- 4.5V on pins 8 and 4 of the opamp (black lead on virtual ground)?

If that looks OK, I would pull the opamp and use the ohms function to ohm out every pin of the opamp socket to ground. Check for the correct resistances. If those look fine, if you have some jumper clips, I would inject signal at the input wires (past the pot) and see if you get anything at pins 1 and 7 of the opamp in terms of sound out. Your pot appears to be wired correctly, and the jacks also appear to be correct (although I would check the datasheet for the jacks).