Handmade Electronics

by James Schidlowsky

More photos of DIY handmade electronic sound (and other) boxes and the construction thereof, including breadboard prototypes, layout stuff, wiring.

Be sure to check out my main handmade electronics page.


CLK-OSC Module

January 2017. A simple clock oscillator module for a collective semi-Lunetta-ish synth at the Eastern Bloc soundLab in Montreal... Some basic square wave oscillators: 2 with inverted outs as well, 1 normal, and one with mark & space control (i.e. adjustable duty cycle), all with 2 frequency ranges.

All made using a single CMOS 40106 hex Schmitt trigger inverter.

animated GIF of CLK-OSC synth module

Ribbon Controller

November 2016. A ribbon controller produces a CV for use with other voltage-controlled modules by moving one's finger on the ribbon.

After building different makeshift ones using resistive video tape and a couple of different systems like suspending the tape above a strip of copper or suspending a guitar string above the tape glued to a surface, I finally gave in and bought a softpot membrane potentiometer by spectra symbol.

It's much more robust than any of my previous problematic efforts, and basically all I did was put it on a board and wired up a bit of hardware for the battery, switch and TRS jack. It can either use the power from another compatible device via the cable or from the onboard battery. A future improvement would be to add a potentiometer for attenuating the output to be more compatible with other devices.

Ribbon controller

Utility Boxes: FACEMULT & HEXGĀT

March 2016. Just a couple of utility boxes that don't make sound but are handy.

FACEMULT: allows MULTiple (4) separate signals to be interFACEd between 4 styles of connector: 1/4, 1/8, banana and bolts. A bit later I added 2 RCA jacks. Handy for interfacing with other synth systems.

HEXGĀT: produces 6 simple gate/clock signals with adjustable rates (from approx 0.2 - 18 Hz) and 1/4 jack outputs and bolts (for use with alligator clips so as to communicate with breadboards). This is simply 6 square-wave oscillators made using a CD40106 chip.

FACEMULT and HEXGĀT utility boxes

Centigrade 37 Pinball Lightbox.

Demo video here: https://vimeo.com/150537040. Completed December 2015.

This is an electronically animated lightbox I made from the backglass of a Centigrade 37 pinball machine made by Gottlieb in 1977. The original machine had an electro-mechanical animation for the thermometer, which consisted of a red ribbon that would crawl up by increments each time one hit certain targets. Instead, I used a gradient of dark red to light yellow printed on acetate and compartmentalised LEDs. When it reaches the top, the tower flashes faster and faster, then the thermometer decrements back down.

I made this for my friends who opened the North Star pinball bar in Montreal in January 2016, which is reflected in the score digits (printed on cardstock, not using actual score reels), as well as their star logo in the credit window. This and the other lightboxes I made are all on permanent display there.

Here are the front and back of the lightbox...

Centigrade 37 lightbox front and back view

* 33 warm white "straw hat" LEDs running on 12V regulated "wall wart" power supply. 16 of them are always on, for general illumination, 16 are for animating the thermometer, and one to flash the tower.

* A PICAXE-14M2 microcontroller is used in conjunction with 74HC595 shift registers and TD62783 transistor array drivers to control the animation.

* A pre-made LM2596 buck converter board is used to drop the voltage down to 7.5V which is then fed to an LM7805 voltage regulator to supply the PICAXE and 74HC595's.

* Some of the logic involves randomness: the length of time between thermometer gradations lighting up and the pause before the animation sequence starts over.

Here's a close-up of the main circuit boards:

Centigrade 37 lightbox circuit boards

Midway "Bull's Eye" Lightbox.

Demo video here: vimeo.com/136931561. Completed August 2015.

This is an animated lightbox I made from the painted plexiglas panel and frame from a "Bull's Eye" wall game made by Midway circa 1972. Before videogames, people used to play these. It was a 2-player dart game with hand controls to select when to release the dart, and it would take one of 3 trajectories and hit one of several spots on the dartboard. All I had was this piece, not the whole machine. I've only seen a photo of the original interior with a bunch of light bulbs and the control mechanism. If you want to see the real machine working, someone posted this video on youtube.

I simplified the action and just have one player throw and the dart follows one trajectory. The bull's eye is either hit or missed.

The original frame and artwork looks like this (approximate dimensions: 130 x 83 cm):

Bull's Eye lightbox front

I built an open box frame to hold the light-panel, electronics and cardboard light isolators, and it's attached to the artwork frame using a piano hinge and a couple of magnetic latches. Here it is with the thing open:

Bull's Eye lightbox panel recto

Here's the back of the light/circuit board panel, with the wiring to the LEDs:

Bull's Eye lightbox panel verso

* 49 warm white "straw hat" LEDs running on 12V regulated "wall wart" power supply. 22 of them are always on, for general illumination, 8 are for the Bull's Eye title letters, which are usually on but also flash when the bull's eye target is hit. The rest are for the hand and dart chasers, and the 2 possible dartboard hits.

* The 2 chasers for the hand and dart trajectory use 74HC595 shift registers and TD62783 transistor array drivers.

* A PICAXE-14M2 microcontroller is used for the logic sequence, clocking the shift registers, controlling the display of the other LEDs.

* A pre-made LM2596 buck converter board is used to drop the voltage down to 7.5V which is then fed to an LM7805 voltage regulator to supply the PICAXE and 74HC595's. I probably could have skipped the regulator and had the buck converter supply the 5V.

* Some of the logic involves randomness: the length of time between dart throws and if the bull's eye target is hit or missed.

Here's a close-up of the main circuit boards. The wires to the LEDs go through holes to the other side:

Bull's Eye lightbox circuit boards

This and the other lightboxes I made are all on permanent display at the North Star machines à piastres pinball bar in Montreal, Canada.


MIDI Expression Pedal Box

July 2015. A friend wanted a MIDI wah-wah, i.e. expression pedal so I whipped this up using an Arduino to process the signal from a potentiometer-based expression pedal, and send the value along as particular control message. It was based on this post I found on codeproject: Arduino-Based MIDI Expression Pedal. Instead of the pedal, one could plug in any sort of voltage-divider thing.

September 2015: New, improved version, pictured here with an M-Audio EX-P expression pedal. Instead of the permanently-wired wallwart power adapter, I used the USB adapter. Also now can plug in two expression pedals, thus controlling two different parameters.

MIDI Expression Pedal Box

Auto-Droner Guitar (Prototype).

3 strings of an electric guitar played by electro-magnetic physical action (i.e. the strings are actually struck). I finally broke down and used an Arduino. It controls the speed of the devices via PWM and slowly changes the intensity of the drone.

A prototype, proof of concept, it was intended for and used as an installation at STABLE that ran for several hours, so the variations are perhaps too subtle to capture in this brief demo video here: https://youtu.be/1-RIjPaMFj8, June 2015.

Auto-Droner Guitar (Prototype)

"Sea Breeze" Lightbox.

Demo video here: vimeo.com/122848906. Completed March 2015

Front and back of a pinball backglass lightbox I made for friends. The electronic circuit controls general illumination, as well as two chaser circuits, one of which changes speed periodically. Sea Breeze was the first of two pinball machine models ever produced in Canada, manufactured circa 1949 by the North Star Coin Machine Company of Montreal, which you can read about in this article. The box measures approximately 61 x 55 cm.

Sea Breeze lightbox diptych

Front view of light panel with baffles. There are 45 LEDs in total: 18 for general illumination, 9 for the S-E-A-B-R-E-E-Z-E "comet trail" chaser and 18 for the scores chaser:

Sea Breeze lightbox light panel front

Soldered boards for power and control circuits:

Sea Breeze lightbox circuit boards

Circuit details:

* Runs on regulated 12V supply. Uses 45 warm white "straw hat" LEDs.

* The S-E-A-B-R-E-E-Z-E chaser is 9 LEDs, and was adapted from Bill Marsden's "comet trails" chaser circuit using a CD4017 and transistor drivers (see fig. 12.3 D on allaboutcircuits).

* The "scores" chaser is 18 LEDs, and uses Bill Bowden's "18 Stage LED Sequencer" circuit with 2 CD4017's, but with 3 ULN2003 transistor arrays to drive the LEDs ( see Bill Bowden's Hobby Circuits).

* There is a mode timer which will enable/disable the chasers such that only one is running at any one time. Diode steering is used so that when the "scores" chaser is running, the S-E-A-B-R-E-E-Z-E letters are all lit.

* There is also a speed control timer circuit for the "scores" chaser, same thing I used in my first pinball lightbox (see "Faces Lightbox" below). This consists of a CD4046 VCO which serves as the clock for the chaser counters. The timer switches between the VCO being fed by a large capacitor, or nothing. When it's nothing, the VCO runs at its base speed, which is set at about 1s. When it switches to the capacitor, the voltage goes from the 12V and discharges in about 30-40s, hence the clock speeds up to its maximum, back down to the base speed.

* The actual mode and speed switching is handled by a CD4053. The timers and clocks (except for the 4046) are good ol' CMOS 555's.

* For general illumination, i.e. the 18 LEDs which are always on (the girls, the bird and the sailboat), there are 6 strings of 3, 2, or 1 LEDs in series.

This and the other lightboxes I made are all on permanent display at the North Star pinball bar in Montreal, Canada.


"Faces" Lightbox.

Demo video here: vimeo.com/91720349. Completed April 2014

Front and back of a pinball backglass lightbox I made for a friend. The electronic circuit controls general illumination, as well as randomly blinking lights and a chaser for the "big eye" which changes speed.

Faces lightbox diptych

"Big eye" chaser light concentrator and circuit board detail. Maintains a slow speed for about 40 seconds then suddenly runs fast, slowing down over about 40 seconds and returns to the slow speed.

Faces lightbox big eye detail

This and the other lightboxes I made are all on permanent display at the North Star pinball bar in Montreal, Canada.

The original Faces pinball machine was manufactured in 1976 in Spain by Sonic.


Populated PCB's for the Pulse Witch 23. The layout's pretty clean here, but then comes the panel wiring and things can get messy!

Populated PCB's for the Pulse Witch 23

PCB soldering, verso, for the Sweet32 Automator. Usually I like to use bussed PCB's, but sometimes it's more practical to do the old perfboard-with-solder-pads thing.

Automator PCB soldering, verso

Populated board for the Sweet32 control box.

Populated PCB for Sweet32 control box

The Clockbox is a small utility device for making breadboarding simpler. I got tired of building power sections and clock oscillators over and over, so I built this little box that gives me a regulated and filtered 9V and four square wave clocks. Each oscillator has 3 different range capacitors, so the box can produce frequencies ranging from about 0.01 Hz to 6300 Hz overall. With some alligator clips and/or wires, I can plug it into my breadboard and away I go! Completed September 2012.


Quad Spacial Percussionizer

Layout diagram. I use graph paper cutouts of the footprints of the different switches, pots and other hardware, then try to find an ergonomic and logical layout that fits a given enclosure.

Quad Spacial Percussionizer layout

Panel wiring:

Panel wiring

Detail of "range" rotary switch with 6 capacitors:

Detail of rotary switch for capacitors

"Lunetta" Synth prototype

Synth based on logic chips, as proposed by Stanley Lunetta. A great way to start making noise with electronics. Visit the Lunetta forum on electro-music.com for more info/inspiration. Alas, I never got around to finishing this beast.

Lunetta synth prototype

4x6 Patch Matrix

Made from six 1x4 RCA jack blocks (scored at Active Surplus in Toronto (R.I.P.)) hot-glued together and using resistor-shorted RCA plugs to make the connections. Also from the early days. I lost interest because I stopped using a lot of effects pedals and I didn't really have much use for it. So I never got around to putting it into a more durable enclosure.

4x6 patch matrix

The Lopsided 2-Channel Auto Panner box.

Not a very good circuit, but it was in my early days of making stuff.

Lopsided 2-channel auto panner box

Classic Passive Ring Modulator, using 4 diodes and 2 transformers. Built into a can of "gourmet powder" which is really M.S.G. (which I did not eat).

Classic passive ring modulator