Page 1 of 1

3 T15's with the same issue, 1 with a different one

PostPosted: Thu Jan 26, 2012 9:08 pm
by jefftd
Hey Tim,

I've recently built 4 T15's, but all of them are non-functional.

Three of them power up fine, test fine for the ±18v points, and have the phantom power test fine, but don't pass sound. One passes white noise when the trim knob is rotated, but otherwise doesn't work.

I know I installed U5 and U6 backwards at first, and have since corrected that issue. Here's a spreadsheet with the readouts of U1-4's pins - I'm hoping that I don't have to replace every single one of them, so if you could let me know which look suspect it'd be most appreciated.



The last T15 has given issues from day 1 - U5 and U6 were installed correctly, but U3 has blown three times now (replaced each time). I'd post a DMM reading for the pins on the rest of the U's, but they flip back and forth between two numbers and never stabilize. It's built identically to the rest of the units, and all of the components match up to the BOM/schematic, so I'm totally confused as to where to go from here with it.

Thanks!

PostPosted: Thu Jan 26, 2012 9:09 pm
by jefftd
I'm too new a member to include a URL with that post, apparently. Here's the spreadsheet mentioned:

http://dl.dropbox.com/u/392637/T15Troubleshooting.xls

PostPosted: Mon Jan 30, 2012 1:22 pm
by tpryan
Can you post a few clear, well-lit photos of the boards, both top and bottom?

PostPosted: Mon Jan 30, 2012 2:16 pm
by jefftd
Sure - here's a .zip folder with them all. I can also upload higher res versions if you need, but it'll end up being about a 50mb file.

http://dl.dropbox.com/u/392637/JeffTD%2 ... %20xls.zip

PostPosted: Sat Feb 11, 2012 12:35 pm
by jefftd
Tim, have you had a chance to look at the pictures? I hate to nag, just trying to avoid multiple Mouser orders if I can.

PostPosted: Tue Feb 28, 2012 11:21 am
by jefftd
Could I please get some kind of assistance on this? Thanks!

PostPosted: Tue Feb 28, 2012 6:33 pm
by tpryan
All I can tell you is pack them up and send them in. Please send an e-mail to rma@seventhcircleaudio.com for return instructions.