[djbob]

Just completed (thought so, anyway) my Mini3 build. Passed sanity check and seemingly all other checks per AMB website. With phones connected I have sound in both channels, however, I'm getting a "scratchy" type of distortion. It' not horrible but it is definitely not tolerable. I've reflowed all connections including 8397 and 690. My ferrites are mounted 1/8 or better so I don't think they are causing it. I'm clueless as to where to look from here. Any help would be greatly appreciated.

Here are the numbers from my Fluke:
Quiescent current - .031a

Railsplitter: V- to V+ - 7.98
V- to IG - 3.964

IG to OL - .0001
IG to OR - .0001
IG to OG - -3.564

Charging circuit test good @ .018a and 11.93 respectively.

Thanks once again everyone.

 

[Pars]

Quote:

Originally Posted by djbob /img/forum/go_quote.gif Just completed (thought so, anyway) my Mini3 build. Passed sanity check and seemingly all other checks per AMB website. With phones connected I have sound in both channels, however, I'm getting a "scratchy" type of distortion. It' not horrible but it is definitely not tolerable. I've reflowed all connections including 8397 and 690. My ferrites are mounted 1/8 or better so I don't think they are causing it. I'm clueless as to where to look from here. Any help would be greatly appreciated. Here are the numbers from my Fluke: Quiescent current - .031a Railsplitter: V- to V+ - 7.98 V- to IG - 3.964 IG to OL - .0001 IG to OR - .0001 IG to OG - -3.564 Charging circuit test good @ .018a and 11.93 respectively. Thanks once again everyone.

That looks bad (if its volts and not millivolts). I'd say your ground channel opamp is blown. Check the build thread on headwize as well.

 

[djbob]

Thanks Pars! I replaced the 690 today and the Mini3 is working great.

I appreciate your help.