Danelectro Black Coffee Metal - stomp switch not working

[Joecool85]

4 years ago I got a Black Coffee Metal pedal, it sounds great and I love it.  About 6 months after I got it the apartment above me (happened while I was in college, own a house now) had a toilet over flow and didn't tell us.  It dripped through our ceiling in our bedroom and got the pedal and my K20-X amp all wet.  I cleaned them up and the amp was fine but the pedal hasn't worked right since then.  The LED will turn on and off when you hit the stomp switch but the circuit stays "on" 95% of the time.  Actually, the day after it happened it was a 50/50 chance if the stomp switch would shut the circuit off or not, now it's much worse and it basically just stays on all the time.

I took it apart thinking it was a switch issue and I took the switch out, it is a DPDT momentary switch.  It appears to contact pins 1+3 and 4+6 when stomped and it's open when not stomped.

1  4
2  5
3  6

Not sure if the switch is busted or what but I was hoping to be able to jumper the switch's spot on the board with a couple wires and make it work manually.  I can't get it to switch from "on" to "off" using the wire, only by randomly rubbing my hand across the bottom of the circuit boards and eventually it will switch, but for the life of me I can't figure out which contacts need to be touched.

The idea was that I could get it permanently wired in the "on" position and then install it in a metal box and use a standard diy wiring scheme with true bypass and a regular DPDT or 3PDT switch.

It also appears to be that the circuit is primarily run on the daughter board that has the tone and volume pots on it, the bottom board that has the stomp switch, in/out jacks and power jacks is attached with a 5 or 6 pin connector and has two small IC's on it, I think maybe they handle the switching but I'm not sure.  Maybe there is a way to make a new parent board or modify this one so that it is on all the time?  Any schematics available for these?

[Ronsonic]

It's been years since I worked on one of those, so my memory is hazy and I didn't do the switching, just added a "cream and sugar" knob for a client. IINM, that series of pedals did have a universal switching/jacks PCB and an effect PCB.

I have done rehousing on others just required diagnosing the conx between the switch board and the FX board and replacing the switching with hardwire switch and jacks.

[Joecool85]

It's been years since I worked on one of those, so my memory is hazy and I didn't do the switching, just added a "cream and sugar" knob for a client. IINM, that series of pedals did have a universal switching/jacks PCB and an effect PCB.

I have done rehousing on others just required diagnosing the conx between the switch board and the FX board and replacing the switching with hardwire switch and jacks.

That would be sweet if I could just replace that extra board with a switch and jacks.  I'm going to see if I can find a schematic anywhere.  Hopefully someone else has some input though, the more the merrier!

[PRR]

Get distilled water, alcohol, toothbrush, and BRIGHT light. Clean every bit of old dry toilet-scum off both sides of the boards, rinse with alky, and put under the light to dry and to LOOK CLOSE for corrupt traces and joints.

> jumper the switch's spot on the board

If it is Momentary, jumpering probably won't jam it into one mode. If you can trace to the flip-flop which does the actual toggling, you can probably booger that into a mode. The flop probably works some FET switches: cutting one and jumpering another will work.

FWIW: Musician's friend has "Danelectro DJ-21 Black Coffee Metal Distortion Pedal" on sale for $27.80. Jus sayin: if I were to fix yours I'd probably charge $2 for the fix and $48 for figuring out WHAT the fix is; a fresh new one is cheaper than the brain-pain to fix the toilet-stained one.

[Joecool85]

Get distilled water, alcohol, toothbrush, and BRIGHT light. Clean every bit of old dry toilet-scum off both sides of the boards, rinse with alky, and put under the light to dry and to LOOK CLOSE for corrupt traces and joints.

> jumper the switch's spot on the board

If it is Momentary, jumpering probably won't jam it into one mode. If you can trace to the flip-flop which does the actual toggling, you can probably booger that into a mode. The flop probably works some FET switches: cutting one and jumpering another will work.

FWIW: Musician's friend has "Danelectro DJ-21 Black Coffee Metal Distortion Pedal" on sale for $27.80. Jus sayin: if I were to fix yours I'd probably charge $2 for the fix and $48 for figuring out WHAT the fix is; a fresh new one is cheaper than the brain-pain to fix the toilet-stained one.

I tried cleaning it up with alcohol and it did work a little better but still not right.  Not worth a lot more work trying to figure it out.  If Danelectro sends me a schematic I may be able to easily bypass the switching portion of the circuit with a regular stomp switch, then it would be worth it.  If not I'll put it back together and give it to my brother (he had been using it just to mess around on while it was stuck "on".)

[Joecool85]

Danelectro got back to me, no schematics available.  Actually, technically it's just that they won't share them - against their policy.  Oh well, so much for that pedal.

If anyone wants it, they can have it for $5 and shipping.

Gone, my brother wants it.

[Joecool85]

Before I put it all together I figured I would write down some specs.

For the switching circuit it uses a CD4013BC "flip flop" chip.  The signal goes into a CD4053BM, then the gain stage is 3 x RC4558.

The RC4558 has two channels each with 300 gain per.  That means a potential gain of 729,000,000,000,000 (729 trillion).  If I did the math right that is about the same as 7 x TL071.  I'm wondering if I could build a 2 x TL074 monster and get the high gain I'm looking for....hmmm....

[Ronsonic]

Danelectro got back to me, no schematics available.  Actually, technically it's just that they won't share them - against their policy.  Oh well, so much for that pedal.

You sure give up easy. 

A signal probe and a DC voltmeter will diagnose the Goes-innas and Goes-outtas of that FX board.

Go on. Be a real man and rehouse.   

[Joecool85]

Danelectro got back to me, no schematics available.  Actually, technically it's just that they won't share them - against their policy.  Oh well, so much for that pedal.

You sure give up easy. 

A signal probe and a DC voltmeter will diagnose the Goes-innas and Goes-outtas of that FX board.

Go on. Be a real man and rehouse.   

No time to fuss with it, too many projects in general but definitely way too many electronics projects.  I chatted with my brother and he's wanted to have a looper box for a while apparently anyway to use as an effects loop on his bass rig so that makes the most sense.  Keep it modular.  Simply have the Black Coffee plugged into the looper and switch it on and off that way.