Schematics

You’ll find a lot of useful schematics here that can be applied to a variety of DIY audio circuit applications!

4093 NAND Gate Oscillator

4093-nand-gate-oscillator-schematic

Description:

Use a NAND Gate to get a square wave oscillator.  Typically, the 4093 is used due to it being a Schmitt Trigger and there being 4 of them in the IC package.  The potentiometer allows for user-adjustable frequency control.  Lots of uses for this circuit building block.

Staircase CV (Control Voltage) Generator

control-voltage-staircase-generator

Description:

Use this circuit with your circuits to output a staircase-style CV.  The 4516 Binary UP/DOWN Counter is controlled by a two 4093 CMOS NAND Gate oscillators; one controls the clock speed, the other controls the direction of the binary count.  A R-2R resistor ladder converts the binary output into a scalable voltage, which is then limited by a potentiometer and buffered for use with synthesizers that can accept a Control Voltage.

555 Monostable Multivibrator

555-monostable-multivibrator-schematic

Description:

The 555 timer can be configured with external components to output a single pulse for a fixed duration.  When the switch is toggled to “ON”, the output will go high/1/ON for a brief moment of time, then go back to its stable state.  You may find that some switches will need to be debounced, which is a pain in the ass reality of dealing with physical components.

True Bypass Passive Ring Modulator

ring-mod-with-bypass-schematic

Description:

A simple 2 Transformer, 4 Germanium Diode Ring Modulator with a true bypass switching scheme.  Includes input for Carrier Wave modulation.  Power is only required for the status LED.

Passive A/B Box

passive-a-b-box-schematic

Description:

A simple switching circuit that allows you to route a signal to two different paths.  LEDs help indicate which signal path is active, although this circuit can also be used without battery/DC Jack power.

Coron DS-8 Drum Synth Clone

ds-8-drum-synth-schematic

Description:

Originally made by Coron, the DS-8 Drum Synth circuit is a fairly complex circuit that generates some awesome analog synth tones.

PT2399 Echo Application Circuit

PT2399 Echo Application Circuit

Description:

Ripped straight from the Princeton PT 2399 Digital Delay Datasheet, this schematic is a great basic circuit to get acquainted with this extremely impressive Integrated Circuit.

PT2399 Surround Delay Application Circuit

PT2399 Surround Delay Application Circuit

Description:

From the Princeton PT2399 datasheet.  A great starting point for experimenting with the PT2399.

Atari Junk Console

atari-punk-junk-console

Description:

A highly modified Linear Feedback Shift Register circuit with a lot of oscillators.  Sounds a lot closer to vintage Atari than the much-more-famous Atari Punk Console.

Atari Punk Console

atari-punk-console-schematic

Description:

The Atari Punk Console schematic.