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I do the same with a veroboard matcher and it works great! To more easily compare JFETs for matching, you can also calculate Rds(on) from: Rds(on) = -Vp/(2*Idss) - I use the terms pinchoff voltage (Vp) and Vgs(off) interchangeably here I usually bulk test my JFETs and add them to a...

Thanks mate, these look great! The 3-Knob & 6-Knob boards are a genius idea. Btw, your site has been super useful, especially the Tayda pot page! Super unique & efficient resource.

For JFETs, it should say something like "JFET N-Ch" at the top, and likely Id or Vg for measured values. If you're lucky, you'll get Vgs(off) and Idss values, and maybe even Gfs.

That looks like 0.15" pitch board rather than standard 0.1" spacing. The wider spacing allows you to more easily use larger "mojo" style components, but is often more expensive. The only options I've seen for sale are from RP Electronics & Vero Technologies. You may want to ask Andy over at...

Oh you're talking about the PNPs, not the JFETs. You're good then.

If you're willing, I'd love to get the gerbers for that! I've tried making my own, but am not great at making custom Eagle footprints.

Oh shit, can you break them by doing that? I have defo gone past the click a fair few times. Lately I've been using a DMM to set multiturn trimmers to the middle of their resistance before installing them. Knowing the starting point definitely makes dialing them in a LOT easier.

JFETs shouldn't have an hFE value, what did you test them with?

As someone who has killed many a cheapo tester, the sturdier & more accurate DCA55 is worth the money if you're looking for a long-term solution. I only wish it could also measure JFET Vp & Idss, as that would make it the standout option over cheaper testers. Unfortunately, only the DCA75 does...

How do the TC-1 Iceo & Ices measurements compare to R.G.'s leakage values?

I use the same one. Decent enough for Ge transistors, here is how I interpret the measurements: Germanium Transistors: hFE - DC Gain - hFE = Gain parameter measured under DC conditions Vbe - Voltage b/w Base & Emitter - (mV) - 0.65-0.7V for Si, 0.15 to 0.3V for Ge. Ic - Collector Current used...

This is the real answer; you won't know until you try. Especially for builds with sockets & drain trimmers, there is no harm in trying different JFETs. For pedals, where distortion is often a desirable trait, the effect of highly variable Vp/Idss specs, headroom & biasing of different JFETs is...

One of the best resources I've found for learning about guitar-specific electronics is Solid-State Guitar Amplifiers by Teemu Kyttälä. It does cover amplifiers, but the "Preamplifier Circuitry" chapter covers many pedal topics. It starts with basic gain stages & filters, but also covers...

Mmmmh, already bracing for what the Ass & Clench switch is going to do...

This post from Chuck gets at a key concept for working with impedances in electronic circuits: the voltage divider. This was a BIG breakthrough for my understanding of impedance, but is only half the story. For the sake of simplicity, I'm going to ignore the reactive components of inductors &...

So I struggled (and still do) with this concept as well. Let's start with this analogy from Zachary Vex, which helped me: "Here's the basic idea: You get on a bicycle, and try to bike up a hill. You are completely frustrated; the pedals will hardly turn & you can't get enough speed to get any...

I've also really enjoyed the DIYRE Colour Palette stuff! I appreciate that they open source most of their designs as well as I've learned a lot through simulating & breadboarding them. Some of those Colour Module circuits just sound amazing for how simple they really are. Unfortunately, a lot...

No problem, I had an iron with that same adjustment and it gave me trouble too. On mine, the temperature dial wasn't great at staying in place, but you should be able to take off the label & tighten the dial screw to keep it from changing settings every time you pick it up. Double check that...

Boutique pedal manufacturers called that a "highly interactive control", and often charge you extra for it! Intermittent problems like that are difficult to solve, but as both the LED and Volume control connect to ground, it's likely a short to ground or mixed up ground wire. The LED cathode...

I just found this thread and I'm really enjoying it. It's nice to see I'm not the only one who's had a few donnybrooks with a breadboard! Originally, I also had 3 breadboards hooked together as an all-in-one protoboard, but it ended up being a pretty inefficient use of them, and I'd end up...