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Timbo did one that runs on a power supply if you can find it. It was probably a year ago.

Great work, cool idea from your friend, too. I actually think it'll sound awesome for leads in a band setting.

I keep seeing a bunch of projects with +18V on an op amp. Come on, guys, live a little. Split rail! It's fewer parts. It MORE headroom by at least a volt. It is every bit as easy. Plus you can do doublers on both rails and blow up some chips! Okay, let's not do the last one.

Discrete component circuits with charge pumps get a pass, because no one likes putting a trimpot on both the drain and source of a FET.* 

That's my rant for the day. Pies may be directed at my face. No rotten vegetables, please.

*But in all seriousness, I guess I could have done split rail with the Hamlet.

Did someone say ... sparkles?

Curtis, since you have that cardinal built up with the work-alikes, would you be willing to experiment with R16, R17, and R18? Try raising those. I'd do it myself, but my breadboards are currently occupied.

It depends on what you're building.

If you're using it in a buffer, there are better FETs. If you're building it in a boost, there MAY be better choices.

If you're building it in an overdrive, there isn't really a good sub for the J201. Their gain is much higher than almost every other FET, and their input headroom is also much lower. This means that when you're cascading them, they produce more gain AND distort easier, so you need fewer stages to achieve higher gain sounds. The closest you can get on pure gain specs without finding something truly exotic is the 2SK170, and they still only have just over half as much gain. 2SK30 is the next step down.

Also, as has been noted in many threads in recent years, through-hole FETs are obsolete and consequently difficult to source. They're going to be expensive. But it's a 50c part ... not terribly expensive in the grand scheme of things. You can also buy SMD J201s and use an adapter board. Chromosphere posted about those recently.

Jimi: The pinout of the MPF102 is identical to the J201.

First, I am by no means saying that there's anything wrong with the workalikes. I buy them all the time and have used them in several projects and almost every time they work great.

The LDR side in the 5C1 and 5C3 clones, by every metric I've been able to measure them, is basically identical.

I HAVE, however, noticed a kind of weird difference. It's in the LED side. Essentially, the LED in the Macron clones works just like a normal superbright LED. The forward voltage is pretty much spot on to a white LED, and it seems to draw the same amount of current.

The VTL5C1s have the biggest noticeable difference. They seem to require less current limiting to get to their brightest point. The measured forward voltage is ... higher than a green LED but lower than a blue LED, at least on the few I have left here. (I used to have dozens, but I used them all!) I got just under a 3V drop on mine.

The result is that under some circumstances, when the ON resistance is critical, just dropping in the Macron to replace the Vactec part might require an adjustment. In the circuit I was messing around with, I got a lower on resistance with the macron but higher dark resistance with the vactec under the same conditions. Extremely similar after testing three of each (so they're also very consistent).

I'm not too keen on cutting open a few $8 parts to see what's inside, but I wonder if anyone has any insight into this, or if anyone's observed something similar.

I'll be xposting this, so if I hear anything else where I'll let people know.

I'm crushed    She says she doesn't really like it.     I showed her how to use the dirt channel on her crate amp and she says she likes that more

She said it sounds like its adding static to the sound. I had to explain that's not static, it's an overdrive. 

Aw, sorry to hear that. But it sounds like your Granny had a typical gear journey: GAS for a highly desirable rare product, inevitable disappointment in its performance. Tell her she should post about it at The Gear Page.

Nice work! Also, the needlepoint under the pedal is very well done.

Your wiring is good for a vero build, but there are some things that will help get it even nicer:

1) When using a metal box and non-isolated (open-frame) jacks, you don't need to run a ground wire from the input sleeve to the output sleeve. The output jack will ground against the enclosure. That's one less wire to worry about.

2) Those X-wing switches have you running wires all over the place. Consider switching to the Alpha-style switches. I know they're more expensive, but Tayda has a clone for $3 that's ... tolerable. It's not just the appearance, though; the other kind of switches tend to feel a little nicer and hold up better than the X-wing switches.

3) When you're planning your enclosure, think about how many wires need to go to one place, and try to drill the box in a way that will result in the shortest wire runs overall. Cut your wires to the right length AFTER you have the PCB situated in the box. (Because you're testing the PCB before boxing, right?) A big thing I see here is the power jack up at the top of the enclosure, off set from the LED, which means you're running wire from the power jack, down to the millenium bypass, back up to the LED. That's a lot of extra wire! And it means running power lines back and forth across audio lines, which can contribute to noise in a particularly noisy distortion effect.

4) Consider using some doublesided foam tap to hold your PCB in place.

5) Orient your pots to get the shortest wire lengths with the least amount of stress on the wires. Think about where they're going to be in the enclosure before you even solder the wires to the pots!

Not to derail the fun, but my point in using a CC license isn't to try and say don't use this. It's the exact opposite really.

Same here. I actually think that expanding the awareness of creative commons and what that means expands respect of copyright in general but also helps people think about where the true value of things lies.

Or maybe I'm just a naive idiot. (It's been suggested in the past.)

There is absolutely NOTHING Jon could do.

Pfttt, this isn't true at all. I can do all of the following:



And



And



Or bad mouth the copier on the forums, because complaining on the interwebs is at least as effective as the rhythm method.

That's brutal.

I thought the pickle was a another modified BMP? but I can see how the single chip might simplify or complicate things. especially the pair that are tied at the emitter. Anything you know of ready to build or at least a vero? (I looked)

Here's a big muff array ...
http://www.diystompboxes.com/smfforum/index.php?topic=106531.0

Compare the datasheets, obviously.

Ho everybody!
Anyone can recommend to me the transistor to use in a building of mangler?
Thx!

For germanium:
Q1 -- you want a transistor with a gain of 40-60 for low gain or 70-90 for normal gain, with as low leakage as you can get.
Q2 -- you want 60-80 for low gain, or 90-120 for normal gain.

You're looking for Q1 to have approximately 2/3 the gain of Q2 to have its bias settle in the proper ~0.5V range.

For silicon, if you can, get a transistor with similar ranges to the above and test them, or use two different transistors that you can reasonably expect to have gain ranges with a similar 2:3 ratio. For instance, the BC series has "A," "B," and "C" ranges, so you could use an A range with a B range and get something that sounds pretty good.

You'll notice I haven't given any parts numbers -- that's because part numbers don't sound like anything. All they tell you is which datasheet to look at, so you have to check the datasheet if you're going to buy a batch of transistors, and you still have to test them if they don't come pre-tested.

Sounds like a lot of work? Fortunately, there are people who will do that work for you.

http://www.smallbearelec.com/servlet/Categories?category=Germanium+Transistors%3AFuzz+Faces+and+Similar
http://www.diyguitarpedals.com.au/shop/index.php?main_page=index&cPath=3

You have to apply heat to both the transistor and diode simultaneously. The diode has leakage, too, and you're protecting against environmental temperature changes, not just in the transistor.

Edit: that's interesting Don.  Why would you say the battery makes a difference?  Does a zinc carbon have a lower voltage (8.4v)?

Different batteries have different internal impedances.

Personally, I think just putting a resistor in series with a power supply makes it sound similar to running on a battery ...