Sviken av elektroniken

Walco Automatic Level Control Schematic

2026-02-17T00:26:00.002+01:00

Today I repaired and traced this thing:

If you see one for sale, keep moving. This things is garbage, and not in a fun way.

I'll make a demo so you can hear it soon. But it really doesn't do much, so you're not missing out.

Maestro Fuzz Phazzer Schematic and PCB layout

2024-04-10T23:55:00.002+02:00

I was recently asked to repair one of these.

The traces on the board break easily, so I had to repair some of those, and after a while I got a nice filter sweep and some distortion. But it would always let through some clean signal even when the balance control was fully towards the fuzz side. Turns out an old battery leak had made one of the sides of that pot always have an extra 20k of resistance, while the other side worked like normal.

I traced the pedal and redrew the schematic that was on the inside.

I hope this can help someone else who wants to build or repair one of these.

Differences between the Musitronics and WD Orange Squeezers.

2023-11-07T04:47:00.000+01:00

Ever since I became interested in the Dan Armstrong effects I've heard that the WD versions were different and not as good as the originals.

A friend recently gave me a WD Orange Squeezer and I just couldn't get it to sound like the Musitronics version I have.

So today I finally traced the WD to see where they differ.

The most obvious differences are that the WD uses an LF351 chip, SK30A JFETs and a silicon diode,

whereas the Dan Armstrong used a 4558, 2N5457's and a germanium diode.

Here's the schematic and PCB layout for the Musitronics version:

And here's the WD:

If you see any errors, please let me know and I'll do my best to correct them.

Yellow Humper

2023-06-02T18:41:00.002+02:00

PCB layout:

Schematic:

I drew all of these based on pictures I found online. Most (if not all) the schematics I could find for these online did not match up with the detailed pictures of the circuit boards I had found. The only original one I own myself is the purple peaker and when I compare that to the copy I made based on the drawings, they sound identical. These really are wonderful effects, some more subtle than others.

My hope is that this will make people build copies instead of ruining/rehousing the vintage units.

Please give me a little credit and Dan Armstrong a hell of a lot more credit if this helps you in any way.

Enjoy!

/Åke Strömer

Blue Clipper

2023-06-02T18:36:00.005+02:00

Schematic:

PCB:

Red Ranger

2023-06-02T18:30:00.002+02:00

PCB layout:

Schematic:

Purple Peaker

2023-06-02T18:25:00.004+02:00

PCB layout:

Schematic:

Green Ringer

2023-06-02T18:21:00.004+02:00

Schematic:

PCB layout:

Orange Squeezer

2023-06-02T18:16:00.002+02:00

PCB layout:

Schematic:

Triangle Big Muff Perfboard Layout

2023-01-17T00:13:00.000+01:00

Here's a layout for the Perfboard triangle Big Muff.

For a schematic go to Kit Rae's incredible Big Muff page.

http://www.kitrae.net/music/big_muff_history.html#TriangleBigMuff

Harmony H1201 Pickguard Template

2022-01-07T18:49:00.005+01:00

I bought a 1966 Harmony Tenor guitar this week that I've started to fix up. It's missing the pickguard so I made a template based on the footprint of the old one and some pictures I found online. Now I'm just waiting for the pickguard material to show up.

Eprom Drum Voice

2021-12-21T17:05:00.000+01:00

Kay Tremolo Schematic

2021-12-12T18:42:00.004+01:00

And remember don't be like Leo,

Tremolo is modulation in amplitude,

Vibrato is modulation in pitch.

The Stromer Mutroniks Superfuzz

2021-10-20T21:51:00.002+02:00

Yashica Electro 35 Pleather Pattern

2021-08-24T23:47:00.007+02:00

I made a pattern and replaced the fake leather on my Yashica Electro 35 GT.

Basic Arduino MIDI Drum Sequencer

2021-07-28T00:04:00.002+02:00

Here's a simple-ish 808/606 style MIDI sequencer. I'd been looking for something like this for years. But most projects were either too complicated or used the arduino to also make the sounds.

So yeah, the one I'm making for myself is more complicated, but here's something to hopefully get you started.

I'm no programmer, but it seems to work.

//Simple MIDI Drum Sequencer 1.0 by Åke Strömer
//July 27 2021

#include <MIDI.h>
MIDI_CREATE_DEFAULT_INSTANCE();

//----------- IN & OUTPUTS ----------

//-------------MatrixMux-------------
#define clockPin 3 //Pin connected to RCLK/SH_CP/SHIFT REGISTER CLOCK     pin 11 of 74HC595
#define latchPin 4 //Pin connected to SRCLK/ST_CP/OUTPUT REGISTER CLOCK   pin 12 of 74HC595
#define dataPin 5 //Pin connected to SER/DS/INPUT                        pin 14 of 74HC595

//---------Knobs and Switches--------
#define clk 2

uint8_t SwRow[4] = {6, 7, 8, 9};

#define shiftSw 10
#define resetSw 11

uint8_t seqLength = 17;
uint8_t trackNr = 0;

//------------ MIDI -----------------
// 808              BD SD LT MT HT MA RS CB HH OH
//                  0    1   2   3   4   5   6   7   8   9 10 11 12 13 14 15
uint8_t note[16] = {36, 38, 40, 41, 43, 39, 37, 56, 42, 46, 48, 50, 52, 54, 56, 58};
uint8_t midiCh = 1;

bool clkProgress = LOW;

uint8_t editMode = 0;
uint8_t stepNr = 0;
uint8_t seqNr;
uint8_t scanStep = 0;
bool dispStep[17] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
//          [TRACK][STEP]
bool currentSeq[16][17] =
{
// 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 SEQUENCE NR 0
{0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0},
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
};

bool resetState = 0;
bool shiftState = 0;
bool lastShiftState = 0;

long time = 0;
long debounce = 300;

void setup()
{
MIDI.begin(midiCh);
for (uint8_t i = 0; i < 4; i++)
{
    pinMode(SwRow[i], INPUT);
}

pinMode(latchPin, OUTPUT);
pinMode(clockPin, OUTPUT);
pinMode(dataPin, OUTPUT);
pinMode(shiftSw, INPUT_PULLUP);
pinMode(resetSw, INPUT_PULLUP);

seqNr = 0;
attachInterrupt(digitalPinToInterrupt(clk), isr, RISING);
}

void loop()
{
mux();
readButtons();
if (clkProgress == HIGH)
{
    stepNr++;
    clkProgress = LOW;
    for (uint8_t i = 0; i < 10; i++)
    {
      if (currentSeq[i][stepNr] == 1)
      {
        MIDINoteOn(i);
      }
    }
}

if (stepNr >= 16)
{
    stepNr = 0;
}

for (int i = 0; i < 17; i++)
{
    dispStep[i] = 0;
}
if (editMode == 1)
{
    dispStep[trackNr+1] = 1;
}
if (editMode == 2)
{
    dispStep[midiCh] = 1;
}
}

void readButtons()
{
shiftState = digitalRead(shiftSw);
resetState = digitalRead(resetSw);

if (resetState == LOW && shiftState == HIGH)
{
    stepNr = 0;
}
else if (resetState == HIGH && shiftState == LOW)
{
    editMode = 1;
}
else if (resetState == LOW && shiftState == LOW)
{
    editMode = 2;
}
else
{
    editMode = 0;
}
}

void MIDINoteOn(uint8_t noteNr)
{
switch (noteNr)
{
    case 0:
      MIDI.sendNoteOn(note[0], 127, midiCh);
      MIDI.sendNoteOff(note[0], 127, midiCh);
      break;
    case 1:
      MIDI.sendNoteOn(note[1], 127, midiCh);
      MIDI.sendNoteOff(note[1], 127, midiCh);
      break;
    case 2:
      MIDI.sendNoteOn(note[2], 127, midiCh);
      MIDI.sendNoteOff(note[2], 127, midiCh);
      break;
    case 3:
      MIDI.sendNoteOn(note[3], 127, midiCh);
      MIDI.sendNoteOff(note[3], 127, midiCh);
      break;
    case 4:
      MIDI.sendNoteOn(note[4], 127, midiCh);
      MIDI.sendNoteOff(note[4], 127, midiCh);
      break;
    case 5:
      MIDI.sendNoteOn(note[5], 127, midiCh);
      MIDI.sendNoteOff(note[5], 127, midiCh);
      break;
    case 6:
      MIDI.sendNoteOn(note[6], 127, midiCh);
      MIDI.sendNoteOff(note[6], 127, midiCh);
      break;
    case 7:
      MIDI.sendNoteOn(note[7], 127, midiCh);
      MIDI.sendNoteOff(note[7], 127, midiCh);
      break;
    case 8:
      MIDI.sendNoteOn(note[8], 127, midiCh);
      MIDI.sendNoteOff(note[8], 127, midiCh);
      break;
    case 9:
      MIDI.sendNoteOn(note[9], 127, midiCh);
      MIDI.sendNoteOff(note[9], 127, midiCh);
      break;
    case 10:
      MIDI.sendNoteOn(note[10], 127, midiCh);
      MIDI.sendNoteOff(note[10], 127, midiCh);
      break;
    case 11:
      MIDI.sendNoteOn(note[11], 127, midiCh);
      MIDI.sendNoteOff(note[11], 127, midiCh);
      break;
    case 12:
      MIDI.sendNoteOn(note[12], 127, midiCh);
      MIDI.sendNoteOff(note[12], 127, midiCh);
      break;
    case 13:
      MIDI.sendNoteOn(note[13], 127, midiCh);
      MIDI.sendNoteOff(note[13], 127, midiCh);
      break;
    case 14:
      MIDI.sendNoteOn(note[14], 127, midiCh);
      MIDI.sendNoteOff(note[14], 127, midiCh);
      break;
    case 15:
      MIDI.sendNoteOn(note[15], 127, midiCh);
      MIDI.sendNoteOff(note[15], 127, midiCh);
      break;
    default:
      break;
}
}

void mux()
{
uint8_t dataToSend;
bool swRead[4] = {0, 0, 0, 0};

for (uint8_t x = 0; x < 4; x++) //Column Scanning
{
    dataToSend = (16 << x);
    digitalWrite(latchPin, LOW);
    shiftOut(dataPin, clockPin, LSBFIRST, dataToSend);
    digitalWrite(latchPin, HIGH);

    //------------ READ SWITCHES -----------------

    for (uint8_t ySw = 0; ySw < 4; ySw++)
    {
      swRead[ySw] = digitalRead(SwRow[ySw]);
      if (swRead[ySw] == HIGH && millis() - time > debounce)
      {
        uint8_t swStep = 1 + x + 4 * ySw;
        if (editMode == 0) //WRITE MODE
        {
          if (currentSeq[trackNr][swStep] == 0)
          {
            currentSeq[trackNr][swStep] = 1;
          }
          else
          {
            currentSeq[trackNr][swStep] = 0;
          }
        }
        if (editMode == 1) //TRACK NR MODE
        {
          trackNr = swStep - 1;
        }
        if (editMode == 2) //MIDI Ch Mode
        {
          midiCh = swStep;
        }
        time = millis();
      }
    }

    //------------ LED'S -----------------

    for (uint8_t y = 0; y < 4; y++) //Row Scanning
    {
      bool thisLED;
      int scanStep = y + 1 + x * 4; //Fast matrix scan

      if (editMode == 1) //TRACK NR MODE
      {
        thisLED = dispStep[scanStep];
      }
      else if (editMode == 2) //MIDI Ch Mode
      {
        thisLED = dispStep[scanStep];
      }
      else
      {
        thisLED = currentSeq[trackNr][scanStep];
      }
      if (stepNr + 1 == scanStep)
      {
        (thisLED) ? thisLED = 0 : thisLED = 1;
      }
      (thisLED == 0) ? dataToSend = B00000000 : dataToSend = (16 << y) | (1 << x);

      digitalWrite(latchPin, LOW);
      shiftOut(dataPin, clockPin, LSBFIRST, dataToSend);
      digitalWrite(latchPin, HIGH);
    }
}
}

void isr()
{
clkProgress = HIGH;
}

Carlin Compressor

2020-10-14T17:04:00.008+02:00

I made some drawings of Nils Olof Carlin's compressor based on pictures I found at Nils Olof's own webpage, the Effects database & Moodysounds. I tried emailing him to make sure he was ok with me posting this, but the email address on his webpage was not working anymore.

I have since heard the sad news that he passed away on August 14 2017. Read more here.

If anyone from his family sees this and wants me to take it down please email me and I'll do so immediately. I hope this will be looked upon as a small tribute to a great genius.

2021 Update:

Carlin Phase Pedal

2020-10-14T15:18:00.005+02:00

I also made some drawings of Nils Olof Carlin's phaser based on pictures I found at moodysounds & the effects database.

I made the traces connected to power red and ground green to make it easier to read.

Price lists

2020-05-24T17:46:00.003+02:00

Pedal price lists converted to 2020 prices:

Electro Harmonix

According to 1974 price list:
LPB-1 was $14.95, $75 in 2020.
Big Muff was $39.95, $210 in 2020.
Bad Stone was $149.95, $780 in 2020.

fOXX

from Sears 1976 fall catalog:
Fuzz Wah Volume was $79.95, $360 in 2020.
Phasing pedal was $99.95, $450 in 2020.
Wah Volume was $39.95, $180 in 2020.
Phase II machine $49.95, $225 in 2020.

Redd fOXX?

2020-05-12T21:20:00.001+02:00

When I was looking for information about the fOXX Tone Machine; this red label version caught my attention. Most foxx fuzzes I've seen have a flocked fuzzy finish, a blue label, a carling toggle switch with on/off plate, and three cosmo knobs. Like this:

But this one has no fuzzy exterior (it looks more like the crinkle finish on Shin Ei pedals), a red label, a switch with no on/off plate, and different knobs. Also note the 9V jack and the recessed foot switch, similar to the Shin Ei SF-1 super fuzz .

I used to have an amp with the same style knobs. The "Global 4080". (aka Harmony 4080)

The red label Tone machine also has a redesigned circuit board.

(There is at least one with the old pcb though)

and that looks a lot like the Global amp and my 1976 Shin Ei SF-1 Superfuzz:

Blue label:

The global amp also uses CTS pots and the PCB says made in Korea.

The transistors (and some of the other parts) look very similar to the ones in the red label Tone Machine.

The second picture is from this listing:

https://reverb.com/item/10501173-foxx-tone-machine-1976

The potentiometers in that unit were made by CTS in late august 1976.

Which is interesting since according to interviews with Steve Ridinger and Dick Norse (from Art Thompsons book "Stompbox"*) fOXX went out of business in mid 1975, and all their assets "were auctioned to someone in Chicago". So maybe?

or Sears?

I looked through all the sears catalogs I could find and the Tone Machine isn't in any of them.

Other foxx pedals appear from Fall/Winter '74 through to Fall/Winter '76.

https://christmas.musetechnical.com/ShowCatalogPage/1976-Sears-Fall-Winter-Catalog/1219

So did this this "someone in Chicago" continue to build foxx pedals with the leftover parts and then have new circuit boards and enclosures made in Asia?

If you know anything I missed here, please let me know.

UPDATE!!

Looks like the mysterious buyer might've been Fred Gretsch Enterprises!

As you can see here Fred Gretsch Enterprises announce to dealers that "We are now exclusive distributors for all FOXX and BALL products and are manufacturing these products here in Chicago."

These pictures come from this old reverb listing:

https://reverb.com/item/1254503-vintage-foxx-guitar-effect-pedal-brochure-3-pages-rare-tone-wah-fuzz-wah

Ok, so I wasn't completely wrong:

"In 1971, he started Fred Gretsch Enterprises, a Chicago-area business that imported and exported a wide range of musical instruments for large national retailers such as Sears, Montgomery Ward, Spiegel, and Aldens. He also purchased equipment from the defunct Harmony Company in the mid-70s and manufactured banjos under the Chicago brand name."

https://www.gretschdrums.com/blogs/gretsch-family-perspective-2018-04-the-fred-thread-four-gretsch-presidents-named-fred-fred4

Here's another interview with Fred Gretsch where he talks about his work in the 70's:

https://msretailer.com/five-minutes-fred-gretsch/

Here's what the "new" circuit boards look like:

And the schematic:

The cap between the base and collector on Q1, and the resistor coming from the 9V are new.

All of the other differences in the newer schematic were there on the original PCB's, but never soldered in.

Also these new boards use ECB transistors whereas the old ones used EBC transistors.

Also check out the Effects Database pages on fOXX:

http://www.effectsdatabase.com/model/foxx/tonemachine#pictures

*https://www.thriftbooks.com/w/the-stompbox-a-history-of-guitar-fuzzes-flangers-phasers-echoes-and-wahs_art-thompson/1521291/#isbn=0879304790

As a bonus here are the four different styles of labels I've found so far:

fOXX Tone Machine

2020-05-09T18:05:00.001+02:00

Four (or more) Transistor Circuits

2020-05-08T18:34:00.000+02:00

Foxx Tone Machine

To be added: Big Muff

Five transistor circuits: Fender Blender
Six transistor circuits: Shin-Ei SuperFuzz

Three Transistor Circuits

2020-04-20T17:22:00.002+02:00

Maestro FZ-1
Maestro FZ-1A

Zonk Machine

Tone Bender Mk 1

Tone Bender Mk 2

Marshall SupaFuzz

Tone Bender Mk 3

Burns Buzzaround

Selmer Buzztone

Jumbo Tone Bender

These are some three transistor Fuzz Circuit Schematics. Like most schematics online, they're probably full of errors.

Two Transistor Circuits

2020-04-20T17:05:00.008+02:00

Tone Bender Mk 1.5
Germanium Fuzz Face
Silicon Fuzz Face
One Knob Fuzz
Goya Panther (Fuzz part only)
Vox Distortion Booster mk 1
Vox Distortion Booster mk 2
Zonk II
Germanium Fuzzrite
Silicon Fuzzrite
UMI Buzz Tone & Volume Expander
Shin Ei FY-2

These are some two transistor Fuzz Circuit Schematics.

One Transistor Circuits

2020-04-20T16:57:00.001+02:00

Dallas Rangemaster

Hornby Skewes Treble Booster

Vox Treble Booster

EH Screaming Tree

These are some single transistor Treble Booster Circuit Schematics.