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Very sweet, and thanks again for helping me get the changes sorted out. Yours looks clean and amazing!

I actually did write down the list of mods needed for the first board to make it work, but as you seemed to have found it's a real big PITA. Several small but impactful mistakes made it not worth even posting, IMO.

Then again, I probably have 60 or so of the bad boards, and not the heart to throw them away.

Another note about R21: I did find a range of values that worked, as you suggested in your PM. They produce ever so slightly different results. I actually like this in a way since it gives you a little leeway to experiment. 2k is what I stuck with in mine.

That's not it either. I just checked. In fact, I had socketed R3 in one of them and toyed with it prior to asking for help. Currently R3 is 1M and R11 is 100k, but no love. What would I change in the power section to drop the votage of VC? It's high on Q1 as well as the IC (right?).

Supply is correct on the IC and transistor. It's definitely the bias supply causing the problem. We just don't know yet what's causing the bias supply to be so high.

Can't really tell: which way is the tab on your metal can IC pointing? Tab should be pin8, IIRC.

Yeah, just recap that at the same voltage. Totally worth the effort, I think. Watch out for any mains voltage that might be residing in there, though.

I had an ME-5 way back in the 80's. Cheesy yet awesome.

Thx, guys 

BTW: it's not terribly noticeable, but that enclosure is actually etched. I had been wanting to try this idea out for a while and it worked out great. I used some cheap paint and a sponge then lightly sponged the paint onto a bare enclosure to create a simple random mask. After it dried, I immersed the enclosure in etchant for about 5 minutes. The non masked areas etch more quickly, so what's left (after you clean it up) is a simulated rusting/deterioration pattern. Completely durable and it looks really neat.

I'm thinking next I will try the same thing, but use an actual CNC to engrave the decal, rather than using a plate like this one. That would be the ultimate!

The Roadrage makes it pretty easy too.  As long as you can find a place to hide it in the box it's a great option.

If you use low profile components you should be able to tuck it underneath the main PCB somewhere.

I tend to use 3M foam tape and put my RR's on the sidewalls, though.

I recommend doing the changes outlined here. It will produce a superior result. It's only a matter of some different values and one added component, so I think it will give you the least amount of headache.

Which reminds me I need to put this info in the doc, too.

At some point I'll break this one out again and tinker with it, but as is with the mods outlined here result in less distortion and a better sounding delay.

I realized a couple of days ago I could do this so I decided I HAD to. I love the way this thing came out. I haven't plugged it in yet since it's f'n freezing in my workshop and my fingers were getting numb. But, worked as expected before boxing.




And no, I won't be making any boards for this one, but yes, I will upload the layout if anyone wants to make their own

Voltages are completely wrong on the IC. You should have 9v on pin7 and about 4.5 on pin3.

Check that you have used 100k for both R10 and R11. The junction of those two resistors forms a voltage divider which should result in about half the supply voltage, or around 4.5v.

I'm gettin a little creeped out ovah here.

Voltages look way off to me. What transistors are you using?

Jeh, got it now. You can pull the bias voltage right off the CP9. The two 10k resistors (to the right of the 9k1 on the schem) form the voltage divider. Tie that to your 10k that connects to the non-inverted input of your TS stage. Or, just add two extra 10k resistors on your daughter PCB tied to the 9v supply and create it's own bias supply. If you do this, use a 10uF cap from the second 10k to ground to give it a little filtering.

Actually, none at all...I'm sorry I'm lost. 

What LM13600? Is the pedal some kind of phaser or envelope filter? What exactly are you trying to accomplish? Sorry----I just can't figure out what you are describing here.

There are tons of small variations on the circuit. That's actually the only schematic I've seen that included an input buffer.

Before doing the newest version, I went back and looked at a lot of different schems and permutations of the Rat and just picked what seemed to have the highest consensus and best sounding version to me. The biasing  resistor position is pretty near inconsequential as far as I can tell (you see it both before and after the 1k depending on whose schematic you are reading!), and the filtering is just, well filtering. You will also see the 4u7 and 1k at the output of the opamp drawn both ways. I think the 22n cap was an omission based on what I thought to be the case in the M'OD (it's been a few years--I honestly don't remember exactly---could just be an error on my part) but I added it back to keep it consistent with the Rat. It probably does some minor tone shaping and influence the input impedance of output buffer, but fortunately the de-coupling is already taken care of with the 4u7 cap earlier. Not having it should not have a big impact, but you could add it in on the older PCB. I'd be happy to draw up a simple mod to do this, if you like.

I've only done laser printed decals in the past, but I generally go about it slightly different.

I go straight from removing the water slide to the enclosure. I very gently (and I mean GENTLE) rub off the excess water and air bubbles with my thumb until I'm sure the decal has good adhesion. Let that dry for maybe 30 minutes or an hour.

From there, 6 - 7 coats of clear. Usually I wait about an hour between (do it on a sunny day with the enclosure under sunlight). By the time I get to the second or third coat, I gently rub the enclosure down with a cotton shirt. This smooths out the finish for the next layer.

By the time you get to coat 6 or 7, the decal edges disappear and you have a thick high gloss finish.