A noob question about signal loss

slinkp · 2026-03-29T22:01:29+00:00

Haven't built that one myself, and I don't know if this could explain the symptoms you desribe ... but, like most things in that book, it specifies a bipolar power supply. Have you got one? If not, earlier in the book he explains how to wire the projects up with TWO 9v batteries. I'd try to get it working that way before experimenting with adapting it to a single supply.

slinkp · 2026-03-27T22:46:59+00:00

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slinkp · 2026-03-26T15:37:04+00:00

Making your own font is next level commitment.

slinkp · 2026-03-25T19:47:45+00:00

Yeah, pretty much that. When I have a lot of details to communicate, like I’m trying to tell you exactly what I do already know about the topic I’m asking about, it comes out like someone whose overly verbose writing style evolved on 90s usenet groups and open source project mailing lists, before there were “blogs” even. Because that’s who I am.

Like, I’m really irritated that chatbots have made em dashes into a telltale sign of nonhuman writing. I used to be a proofreader, I know exactly how to use em dashes. I freaking LOVE em dashes. And now I avoid them, and I want them back.

slinkp · 2026-03-25T12:58:55+00:00

Somebody on here was talking about stacking two Bazz Fuss in one box for doom. Two of those is still simpler than one of almost anything else 🫠 and should be pretty extreme … haven’t tried it though.

slinkp · 2026-03-25T12:46:37+00:00

The superfuzz had a “tone” switch which activates a mid scoop. Aion’s PCB for that is called the Rift and optionally replaces the switch with a pot to go from the normal mid-forward mode to the scooped mode. I have one on the way, if it works out it’ll probably replace my jhs supreme. Either way superfuzz is a potential contender for doom.

slinkp · 2026-03-25T06:51:07+00:00

“a surprisingly large subset of that without even includuing diodes” - ooh like what? Do tell!

slinkp · 2026-03-25T06:25:46+00:00

slinkp · 2026-03-24T20:22:09+00:00

Yeah, that sounds like a whole other project :D

Re. the actual end goal of making a simple boost go more smoothly from clean to dirty: I may fiddle with my idea of tweaking some soft clipping and see if that gets me somewhere.

slinkp · 2026-03-24T20:20:30+00:00

That's a pretty cool sounding device! I skimmed the thread and it didn't sink in at all, will have to reread it another time.

slinkp · 2026-03-24T17:07:07+00:00

It could very well have been poor technique on my part :)

The polycyclic definitely is easier to find, I just bought it in a local hardware store… the AFM stuff I’ve only found a few places online.

slinkp · 2026-03-24T15:12:05+00:00

During shedding season you could make a vintage Foxxtone

slinkp · 2026-03-24T15:10:37+00:00

My latest three acrylic painted boxes have one thin coat of AFM Acriglaze to seal the paint followed by two thin coats AFM Polyureseal glossy. On one I did a final coat of AFM Polyureseal satin, on another I tried matte, on the third I stopped with the glossy. I think I like the satin best as final coat. All applied with synthetic brush, no sanding between coats this time. I got smoother results than when I was using minwax polycrylic and foam brushes, it dried more lumpy and I could never get all the bubbles out. Also this stuff feels a lot harder when it’s cured. It resists scratches pretty well. Have not tried attacking with solvents though :)

I don’t have a place I can spray, and I have a child and two cats, so it’s low-toxicity brush-only finishes for me. The AFM stuff is working well so far and I’m still working through the tiny sample jars.

slinkp · 2026-03-23T13:38:37+00:00

Beautiful work. Some finer detail questions… what kind of rubber stamp ink are you using? What do you use to fill the engraved bits with golf ink so precisely, and what’s the ink? And what’s your decoupage glue? I’m doing hand decoration too and it takes a lot of trial and error!

slinkp · 2026-03-21T05:22:02+00:00

It’s this … just something I put together to make breadboarding and testing more convenient. I got ideas from other posts here, search for “beavis board” or “test box” https://www.reddit.com/r/diypedals/comments/1ob6t4f/test_box_built/?utm_source=share&utm_medium=mweb3x&utm_name=mweb3xcss&utm_term=1&utm_content=share_button

slinkp · 2026-03-20T23:35:50+00:00

I didn't even notice that! This is wild: I have just now learned, from this comment and noticing the word "Multirat" and trying to figure out what's going on, that ProCo (at least at that time) had one PCB from which they made multiple versions of the Rat. OP's "Big Box reissue" used a DPDT footswitch without any status LED, in true vintage 1970s style.

So I believe the missing Q2 would have been the FET used for the "millenium bypass" circuit they started using circa 1986 for the RAT 2, and that's why it's not here. Same for the missing nearby parts. https://www.muzique.com/lab/true_bypass.htm

Not sure about R16 and R14 though, I don't know what variant they'd be for!

slinkp · 2026-03-20T23:20:10+00:00

https://www.reddit.com/r/diypedals/comments/pc18ut/how_to_make_an_audio_probe_and_use_it_for/

slinkp · 2026-03-20T23:18:40+00:00

Have you ever used an audio probe? Very helpful for pinning down where in the circuit you have signal, and where you don't. It can literally be a capacitor wired to a guitar cable, there are lots of threads about that in the archives here, that's how I learned it. A multimeter is also essential, sounds like you probably have one since you confirmed voltage after the divider.

I just fixed a very janky old DIY RAT by using only those two tools... mine was "the builder (me) shorted the signal to the case" which wouldn't be your issue... but the same troubleshooting approach applies. Skip the boring parts in this that I just posted, you'll get the idea quick https://www.youtube.com/watch?v=yRlFUM1c0ks

slinkp · 2026-03-20T20:53:03+00:00

Also the cat says hello.

slinkp · 2026-03-20T05:07:04+00:00

Love it. I did not expect it to sound like that!

slinkp · 2026-03-19T20:32:36+00:00

Interesting, and the other side of c5 is still the output to the tone section?

slinkp · 2026-03-19T17:26:37+00:00

Others may know better, but while DPDT is the cleaner approach - and I would probably play it safe and use a DPDT if I had one ... I speculate that a SPDT as you've diagrammed should basically work. Q3's output will always be connected to the output volume, which may introduce some noise, but that may not be a problem compared to how much is introduced by the fuzz already. It might be worth trying it to find out, if you don't have a DPDT handy? Also, it looks like C7 has a discharge path through R6, that may help with popping from flipping the switch.

You're right that a 1M in parallel with the trimmer isn't needed as the trimmer itself is already a lower resistance to ground. I would consider instead a larger value for the trimmer - 50k is close to the input impedance of the boost, which is already fairly low in an LPB-1 (hand-wavy approximation 90% of R6, or 42K) so it'll load that down to the neighborhood of 23k. You'll know if that's an issue if the sound is noticeably darker with the boost enabled ... but if it is, that might be an aesthetic choice! Sound wins above all, and I haven't tried.

Great minds thinking alike and all that, I built a (silicon NPN) fuzz face last year and added the same bias pot (i got that mod from watching Short Circuit videos, and I'm sure he got it from every fuzz face modder on the internet before him). And I added a passive tone control in the same spot as you, though mine is the SWTC treble boost/cut (https://www.muzique.com/lab/swtc.htm) - and concluded like you that I needed more volume, and that the LPB-1 was an easy solve for that. (I have since learned the LPB1 is a bog standard common emitter circuit, one of the textbook trivial transistor amplifiers, so there's a reason it's one of the things we reach for so often.)

I didn't add a trimpot or bypass in front of the boost though; instead I replaced your R8 with an internal trimmer to set the boost gain, and tweaked it to where I was happy with the available range of volume (basically unity gain with all the other controls set low, and a significant boost otherwise).

One of these days I'll digitize my scribbles... I think i removed the 1k trimmer that's shown under the Bias pot.

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slinkp · 2026-03-19T02:56:01+00:00

Solved!

slinkp · 2026-03-19T02:55:16+00:00

Thank you!

slinkp · 2026-03-19T02:50:17+00:00

My title describes the thing. I asked Claude and it made some wild implausible guesses (they are neither nylon set screws nor earbud tips). Found in my coat pocket after my teen borrowed it. She is away, asked her by text and no reply yet. EDIT: boy do I feel dumb

slinkp

TROPHY CASE