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If the signal has disappeared at q1, maybe check that there isn't any short to ground around c37.  Test if q1 is shorted directly to ground?

No shorts.  Putting it away and giving up.  It's not worth the time and I don't have the expertise to run down the problems.  Thanks for the suggestion.

And channel 1 does not work at all.  I'll get to that leter.

If the signal has disappeared at q1, maybe check that there isn't any short to ground around c37.  Test if q1 is shorted directly to ground?

Thanks.  That never occured to me.

Got back to this. (Referring to lab5-schem-2)  Looking at the  Master Volume, Compressor, Outout part of the schematic.  I have trace a very good clean signal to R76.  I get signal on both sides of the resistor.  I still have a signal into C36.  Now, assuming I understand the schematic, there is no signal anywhere in Q1.  There is continuity from C36 to the bottom leg of Q1. I have replaced C36 as well.

Is there anything else to check? 

2-1ufs will work. That's what's on mine.


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I don't think 2 1u's will work.  I tied the 2 negative leads together on 2 4.7uf eloctrolytics and got almost exactly 2.2u.  The sites I saw said that wiring caps in series halves both of them.

Just realized I don't have one.  Some research shows that 2 polarized in series (net to net) should work.  I measured it and the capacitance is correct.  Anything else I need to know?
Thanks

I haven't even bothered to go to the new GC in Laurel. If I'm going to a store it's Bills or Appalachian Blue Grass for acoustic stuff (except they don't carry breedlove).

A good friend of mine works at Bills so I try to go through him when I visit there. If you ever stop in, ask for PJ. He's super cool and he'll hook you up.

Love Appalachian.  Bought a Taylor there last year and have an eye on a 12 string.  Oddly enough I've bought 3 guitars from PJ:  LP, Tele, and a Ric 330/12.  But I'm less than impressed with the guitar techs there.

What surprised me is they just opened a new one in Laurel,MD in October.  It looks like every other one.

Pretty sure it's been there a long time, but closed for a bit while they did a remodel.

Could be wrong, don't get up that way too often.

The ones in VA just outside DC had a very noticable decline several years back. Now they are dirty and don't have much beyond strats and les Paul's.

You may be correct but it never shown up in searches for music stores before.  It's so generic it could be the one in Pasadena, CA I've visited.  It's either Make n Music in Frederick or Bill's in Catonsville if I need something.

What surprised me is they just opened a new one in Laurel,MD in October.  It looks like every other one.

If only there were a commercially available PCB one could use!

http://www.rullywow.com/product/glasshammer/

I really like the Glass Hammer.  About 20 bucks in parts and 2 hours to build and box.

"The 4, 5, 6, and 8 are connector pads for wiring one of the switch boards. The other switch board uses Letters instead. "

That's what I thought.  So I am assuming C4 connects directly to lug 4 of the bypass footswitch, I assumed it's that switch.  I'll have to trace the channel switch to.

Thanks Somnif!

Had some spare time.  A question about the schematic (see link above).  To the right of IC1 are 4 symbols labeled 4,5,6,8.  What do they represent?  I always have a good signal out to C4.  Nothing after it except I had good signals all over the board for about 2 minutes yesterday.  Not sure what happened to make it work/mot work.  Sounds like something might be loose.

I have only been working with channel 1.

Thanks for any responses.  I know I;ll have a couple more questions.

Thanks.  I'm off work this week so I will start looking at it in depth.  Considering that many of the traceable points have a signal, I'm optimistic.

I finally got back to looking at this.  After replacing the 2 voltage regulators I'm getting sound at various points in the circuit but still none at the output.  I am measuring 21.5vdc volts at the test points and not 15vdc.  I'm getting 21.5vdc at IC1.  The output of IC1 is fine.   I'll re-check the power section to make sure I have the correct parts.  The 21.5v makes me want to make sure of that.

I've got to study the schematic for the various trace points and go from there. 

Thanks.  I suspected there was a rectifier.  And yes, I measured voltage right out of the power plug. 

As an aside, I wonder why they just didn't go with DC power the whole way?  Those regulators get pretty hot.