Cherry Bomb help please

[amunderw]

Hey guys,

I am doing the Cherry Bomb.  I have everything on board put together and I always test the board and parts with a little testing rig I have built and have successfully used on several other builds before wiring the jacks and switch.  When I tried this board, I do not get anything....  I have gone through the parts one by one twice to check value and orientation where necessary and all checks out to be good.  I also have checked the back several times to look for any solder bridges and I don't see anything even close.

I am baffled on what to do.  Do you guys have any suggestions/recommendations?  If you have any questions, or need more pictures, please let me know.

Thanks

[amunderw]

Another..

[amunderw]

Another..

[jkokura]

Have you tried working with an audio probe and have you taken any voltage readings? At this point that's the next step to try and see what sort of readings you would get.

Jacob

[Om_Audio]

I would get some solder wick or a pump and clean up the back- remove all extra solder and make sure there are no bridges. If you do, be sure to have the iron nice and hot and get in and out quickly as heating things up a 2nd time can bring it's own set of probs- but you are not removing/replacing any parts so that is good.
Good luck!

[amunderw]

Ok, so I'm sorry but I am a halfway noob.  I have built 8 or so pedals but have yet to need to probe anything.  I have a DMM but do not know where to probe at.  Could you please inform me as where exactly the points are that I should check.

Thanks for the help!

[Om_Audio]

Read through these- will help a lot-
http://www.madbeanpedals.com/forum/index.php?topic=1140.0

see the "how to build audio probe" sticky here- you will need to create an account to view it:
http://www.guitarpcb.com/apps/forums/show/3183098-tips-tricks-and-tutorials-builder-s-manual-for-guitarpcb-boards-

[amunderw]

Just what I needed, thanks a lot, and I'll let you know how it turns out in the next couple of days!

Thanks!

[mgwhit]

What kind of transistors did you use?  Can you post the voltages on each pin for Q1, Q2 and Q3?

[amunderw]

I ended up using a 2N3904 for Q1 and Q2, and a 2N2222 for Q2.  I went to test for continuity using an audio probe and didn't get anything after Q1.  I just tested the values for the trannies.  I do not know much about them, but the values for Q1 seem low.  Do you guys think my Q1 is just bad or what??

Q1:
.88
.25
.14

Q2:
8.46
.88
.28

Q3:
6.50
1.42
.76

[mgwhit]

Don't blame your Q1 until you've at least cleaned up the solder joints on the Q1 emitter and the ungrounded end of R2.  Both of those look like they're bridged to the ground plane.  (Although, since you've socketed, you can always swap and test.)