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Put the sweep at minimum and try both range settings. Any better?

Make sure R14 is 330R, not 330K. This would make the attack so long it wouldn't really do anything.

Depends on the gain, but anything above 300uA is pretty high for a transistor of 100hfe or lower. 500uA is about the highest I'd ever consider using for anything up to ~130hfe, EXCEPT in a circuit that requires leakage current to function, like a TB MkI or MkII, or for lower gain leaky pieces, the Harmonic Percollator. So don't just chuck leaky transistors. They might be useful. They will also work as diodes if they're ridiculously leaky (1mA or so ...).

Remove the resistor and measure it with a multimeter, not your eyes.

Attack time on the Bearhug is ~<5mS (it changes depending on the decay setting and depends on the output impedance of Q2, which is a couple hundred ohms if anyone wants to do the calculation). Decay time is 103.4mS in short and 573.4 in long. I honestly have no idea what the ratio is, but it's not extremely high, and it would only be a ballpark figure anyway. Input impedance is ~5M, and output impedance is ~100R-10K.

For the Demeter, look up the turn on and turn off time of the VTL5C10. Those are your attack and decay times. The ratio is based on the on:off resistance of the VTL to any voltage divider preceding it. You can calculate the ratio of pretty much any optical comp the same way.

Attack in the Lovesqueeze is also <10mS, and probably <5mS, again, depending on the output impedance of the op amp (a could hundred ohms?).

Edit:
Decay calculation is uF * Kohms = mS. 1uF * 100K = 10mS. If there's no obvious resistor in parallel with the hold cap, use the input impedance of the next stage.
Attack calculation is (R1||R2)*C (per PRR and Merlin)
Max ratio is always gain at idle/minimum gain.

CJ's cool little vibe/phaser/filter effect. I modified it to have a rate LED, and made some adjustments to use a super bright LED (though in the end I probably would have been fine with the regular red LED). I also used an on/off/on switch for the mode, so it has a mode that's just the two wobbletrons in a row.

Sounds pretty cool. The "big cap" mode, which I labeled filter, is very unusual, sort of a cross between a filter and phaser effect, and I think the project is worth a build just for that mode.

Literally the only thing I would have considered changing about this is to change the output buffer to a gain stage and have an output trimmer or volume control. On lower depth settings, I have a very small volume drop, though it's at unity otherwise.

I wasn't sold on the knobs, but cream was just wrong, the enclosure wasn't "white enough" to use refrigerator white, and chrome didn't look right.



Brian's Grease Gun, with a germanium transistor and a pair of OA126 diodes.

When I moved it from the breadboard to the PCB, I made some changes to the coupling caps -- the output cap was overkill, and there seemed to be something wrong with the decoupling cap after Q1 -- it was 2n2 in the original, but there was only a very tiny bit of signal coming out of there, even though the calculator says that it should pass most of a guitar. I ended up just using 100nF for every coupling cap in the circuit and it's a very dirty boy now.

Finally, in addition to the germanium transistor in Q2, I also decided to just use a BC549C in Q1 because the input impedance was bellow 500K, so there was no benefit IMO to using the (more expensive) MOSFET. Incidentally, the joke on the enclosure about magical germanium is a nod to there being almost no difference in sound here between the BC549C and the germanium in Q2 and that the OA126 diodes have the same Fv (and thus sound basically the same) as the 1N914s called for.

I'd recommend this one with the caveat that you should be prepared to try a couple different values in place of that 2n2, and to think of the pedal as more as a roleplayer.

What's it sound like? Kinda greasy. No, really. The treble cut on the tone knob is fairly deep, and the feedback diodes are a little spongy sounding, and it also gets pretty dark on lower gain settings. It sounds really cool pushing the yellow channel on my Hot Rod Deluxe, and it also sounds pretty neat stacked after something else into the rhythm (blackface) channel on my Imperial. I know Brian plays an AC30, so I suspect that the tone knob's extremeness is very friendly with a cranked vox.

Excellent faceplate! The giant lens looks really cool, too.

We gotta talk about your pots' wire lengths, though. It'll really tidy things up on the inside if you make them shorter.

Do you mean Mythic Overdrive? It's made by Comfort Player. He posts on BYOC. It's a Klone, and a very well made one.

DO NOT USE THE 18V ADAPTER WITH A KLONE. You will blow up a critical component if you do.

The power adapter has nothing to do with picking up radio signals. It also probably has nothing to do with the pedal construction, circuit, or really anything else. It just happens sometimes. It could be from any number of sources, and it could be your guitar and the pedal was just amplifying it, or amp producing it.

To start with, make sure you use twenty times as much wire as you need for the hookup and wrap the board in electrical tape and practice the questionability of your soldering.

In all seriousness, there's a thread on DIYSB, and the long and short of it is that there's nothing different about it except some adjustments to the lamp, which you can make with the trimpots in Madbean's Harbinger.

Phase shift oscillator and bias modulation.

Almost the same as what's in Fender amps -- the EA Tremolo will sound pretty much the same.

This is what I e-mailed to Greg weeks ago:

I need something way more exact than you can give me with a handheld camera. You need to remove the PCB from the enclosure, put it traces-down on a scanner, and send me that. It's the only way to ensure that there is no variation in placement and sizing.

Greg, I don't mean to air any dirty laundry, but you never sent the scans that you told me you'd send, and that was over a month ago. I honestly don't know if I'd have the time for it now, but if you post them here, maybe someone can take up the project. Get 600 dpi color scans.

EDIT: Actually, I just tried to boot up Photoshop and our copy isn't functioning anymore for some reason. I think it's "obtainable" somewhere, though ...

I didn't think the PT2399 even capable of delay times above about 800mS regardless of using the wrong part ...

Post a picture of the PCB. Take voltages. Read here.

huh, I've never seen a bi-color LED with only two legs. Sounds useful.

I hate to say it, Mike, but PRR's answer was the one I would have given since most people aren't going to have this part in hand. If you really don't want to use a socket, you could tack solder it until you know if it works.

That's a fantastic paint job! Great job, man.

Obligatory OMG 4000 posts edit.

If you're happy with the amount of compression you're getting (bearing in mind that it's a fairly mild compressor overall), you could use a different taper for the potentiometers. You could use a linear for both, or even a reverse log for the compression control.

R9 is merely a limiting resistor to partially set the threshold of the envelope. The only way it's part of the problem is if it's not actually connected to the op amp. It could be a jumper.

You're going into an inverting op amp stage after that; I think you won't hear audio signal there (someone correct me if I'm wrong, but I seem to remember that being a thing). You would hear something on pin 1 or on the range pot, though, I think; it should have crossover distortion (it's rectified).

Set your multimeter to 2v. Strum and measure at the attack pot 1. Do you see a voltage change? If not, you need to work backwards. Chances are your op amp is fine, because you have clean signal and half of the op amp is used for that. Check D1 and D2; they create the rectified signal. Make sure they're still working, not shorted, and not facing the wrong way. If you are getting a voltage at the attack pot, then your problem exists after it. Keep following the schematic.