I apparently have a thing for delay/reverb circuits. I decided to do a true stereo reverb using PT2399. It's based on my Spare Room design, but it takes advantage of of the ability to cross feed the left and right signals and to do some cool cross channel-dependent modulation. It's not a small circuit by any measure. In fact, it may be the most complicated single knob pedal in the DIY world, but it's a fun one. The schematic is too big to post at reasonable quality here, but I put the short...

PDF: ETI-1980-04-80 UK Preamp and Power amps.pdf
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ETI-1980-04-80 UK Preamp and Power amps 1.jpg ETI-1980-04-80 UK Preamp and Power amps 2.jpg ETI-1980-04-80 UK Preamp and Power amps 3.jpg ETI-1980-04-80 UK Preamp and Power amps 4.jpg

hey guys
i just built one, i tried a lot of transistors and finally got some nice sound out of it. bias voltages are ok, no ugly noises on the decay
its gated in a nice way, with a hint of octave up when i back the guitar vol pot a little....
what bothers me is on a certain combination on the guitar volume pot and the fuzz''/ bias pot in produces a kind of octave down sound which is actually very pleasant
my question is whether this is normal. i havent heard of a zonk pedal doing this

i...

So I have a DL-4 that powers on maybe 1 out of 10 times. When it does power on, it works totally fine and indefinitely. Sometimes if I unplug it after working then plug it back in, it works. Most of the time it doesn't. After that, it seems like 2 consecutive times powering up is the limit. I've reseated the Eprom several times and thoroughly cleaned the pins. I reflowed all of the pins of the socket. I reflowed a few ICs around the Eprom to see if something was just making a bad contact. I've...

I have built an old favorite from this board, the Highway 89 from Doug Hammond. This pedal kills. The tone is rocking and ballsy and the clean up is great!!

I was trying to let the other guitar player in my band use it and I discovered a really strange issue that we have tracked down to a power issue generally but do not know specifically what the problem is.

When it is powered from my old dinosaur SKB pedalboard the pedal works fine, as it does when I use a single Boss PSA 120 style...

I got this unit in and it sounds great on the bass

I was expecting more of an Overdrive unit but I got a distortion pedal. Sounds also great on guitar!!

Trex - Bass Juice.JPG

Hi all, my line6 m13 has blank lcd screens. The colours still change and the effects all still work. But unfortunately the lcds are either blank or sometimes all black. Looking online it seems like a few people has this issue but I haven’t found a way to repair it yet.
Does anyone have any advice? Thanks

This is side A of the Duellist dual pedal released as a standalone effect. It's got a couple of changes from what's inside the Duellist, but overall pretty close.

king_tone_soloist_trace_schematic.png

Basically a stripped-down Tube Screamer (Son of Screamer) with several tone options.

Full tracing journal: (includes Duellist and Heavyhand)

PCB:

This is side B of the Duellist dual pedal released as a standalone effect. It's got several tweaks & added features from what's inside the Duellist, so not a direct clone, though pretty close.

king_tone_heavyhand_trace_schematic.png

Basically a Bluesbreaker/Prince of Tone with a clipping diode switch and a few different pre-clipping tonal options.

Full tracing journal: (includes Duellist and Soloist)

PCB:

Hello all,

does anyone know this pedal Effettidiclara AGATA from Italy?
It is a boost/driver with 2 gain stages.
Does anyone have a schematic or an idea what kind of circuitry might be inside?

BR Stingray

I've been looking at the Marshall shredmaster for a while, but as used gear prices have reached questionable highs I'm looking at alternatives. I have heard the Truetone Jekyll & Hyde is a TS-like on the overdrive side, and based on the shredmaster on the distortion side.

Do any of you know how different the Truetone and Marshall pedals are? Is it a direct clone? Just wondering if it's worth getting the Marshall.

Here's an odd one
made in Italy, with help from Gary Hurst.

FP1.jpg FP2.jpg FP3.jpg FP4.jpg FP5.jpg FP6.jpg

PDF: Electronics-Today-1987-05-OCR-Page-0050.pdf

Electronics-Today-1987-05-OCR-Page-0050.jpg

This one was a tricky bugger.
I am quite unsure about the accuracy of the trace, since I omitted all switching, but here's my shot at it.

Seems to be fairly similar to the Boss DS-1, missing one gain stage that gets added at the end. Horrid sounding crap through my Laney, even the abominable stock DS-1 sounds slightly better than this. But again, will tinker with it and see what mods are doable 8)

This 2nd gen of Arion pedals incorporate a second output with the ability to switch between...

(｡･∀･)ﾉﾞHi everyone, good morning, noon, and evening
I made a relay bypass version of bd2
IMG_20220327_1709A42.jpg

Schematic_BD-2 RealyPass_2022-04-29.png
Here is the schematic

wx_camera_1648264818689.jpg
This is the pcb for decoration

wx_camera_1649928022863(1).jpg
wx_camera_1649929766720.jpg
mounted on the circuit board

Boss BD2 RealyBypass.zip
As well as circuit board fabrication files, and schematic drawings in PDF format

Full article on gain control in PDF: Electronics Today AUS 01 1979 Gain Control Fuzz.pdf

Electronics Today AUS 01 1979 Gain Control Fuzz.jpg

Sorry to :beatdeadhorse: , but I love Zonk machines! No one likes the sound of the Zonk II (including myself, until now). To me it sounded dark and had a weird abrupt cutoff about the notes...especially lower power chords and the higher single note runs. I attributed this to just being a crap circuit, but after adjusting the bias I changed my mind. I replaced the q2 collector resistor (10k) with a pot (as close to 10k as you have.) I used an audio pot, but a linear would probably work better. I...

PDF: Le HAUT-PARLEUR n°1441 - 7 Février 1974 Fuzz tonalité.pdf

Le HAUT-PARLEUR n°1441 - 7 Février 1974 Fuzz tonalité 02.jpg Le HAUT-PARLEUR n°1441 - 7 Février 1974 Fuzz tonalité 03.jpg

Dear all,
somebody have the schematics of this stomp box?
I found one but it doesn't work and I'd like to repair it.

Radio-Electronics-1963-05-OCR-Page-0069.jpg

The French article that was the source for this circuit, seems to be:
AMPLIFICATEUR GUITARE 5 W (ECC83, ELL80 , EZ80), BF REALISATIONS (p. 46 dans Le Haut parleur n° 1061 mars 1963)
But it's sadly not available digitally, as far as I can tell.

PDF: HP1656_05-1980 Pedale fuzz sustain noise gate.pdf

HP1656_05-1980 Pedale fuzz sustain noise gate 01.jpg HP1656_05-1980 Pedale fuzz sustain noise gate 02.jpg HP1656_05-1980 Pedale fuzz sustain noise gate 03.jpg HP1656_05-1980 Pedale fuzz sustain noise gate 04.jpg

PDF: ETI-CA-1980-01 Struss Fuzz.pdf

ETI-CA-1980-01 Struss Fuzz 01.jpg ETI-CA-1980-01 Struss Fuzz 02.jpg ETI-CA-1980-01 Struss Fuzz 03.jpg

PDF: Electronics-Today-1990-06 Fecko Box Fuzz Echo.pdf

Electronics-Today-1990-06 Fecko Box Fuzz Echo 01.jpg Electronics-Today-1990-06 Fecko Box Fuzz Echo 02.jpg Electronics-Today-1990-06 Fecko Box Fuzz Echo 03.jpg Electronics-Today-1990-06 Fecko Box Fuzz Echo 04.jpg Electronics-Today-1990-06 Fecko Box Fuzz Echo 05.png

Low gain fuzzy overdrive “Schlager.Fuzz”

I like to present an overdrive / low gain fuzz—a lockdown project:

Starting from a fuzz face with lower beta germanium transistors, a fuzz circuit was tweaked to lower gain, softer clipping and the ability to handle (fat sounding) humbuckers:

schlager_fuzz_realized_en_grosz.gif

Low cut / mid boost including low cut control was inserted before input—to allow using guitars with “fat” pickups.

Low cut condenser value / low cut frequencies could be...

Here’s a PCB I made that uses the part numbers from the Big Muff Page. Find a schematic there and populate this board!

Here is an Elk Electrosound I did.

38FF0F4D-0D89-43CA-9658-8BBB38FD5866.jpeg 7CC55625-2FE1-4487-AF41-0EDDB66802E9.jpeg 00C23CAB-21FB-4B80-8C83-E21F43CFF264.jpeg