- Five stereo inputs, switched with Panasonic TQ-2 relays
- One stereo output
- Controlled with ESP32 or rotary switch
- Space for the ESP32-DevkitC/NodeMCU, with break-out for all pins
- IO pins go high when activating a relay, can be used for indicator LEDs
- Power/GND for ESP32 and relays separate from signal power/GND
- Pin distance for power and signal input/outputs: 5.08 mm / 0.2"
- Pin distance for optional rotary switch: 2.54 mm / 0.1"
- Fully open source, no strings attached
Schematics and Downloads
- ESP32 Eagle library: https://hackaday.io/project/46280/log/87314-esp32s-devkit-eagle-library
- Schematic (with ESP32): https://hackaday.io/project/46280/gallery#a3e1b4be8cf593af3733282c43617b2c
- Schematic (without ESP32): https://hackaday.io/project/46280/gallery#cbabb3ed6913ae0336a70ea0561f796d
- Component list/Mouser shopping cart: https://hackaday.io/project/46280-muffsy-stereo-relay-input-selector#menu-components
- Eagle project files and Gerbers are available in the files section.
- Simple example sketch: https://hackaday.io/project/46280-muffsy-stereo-relay-input-selector/log/136019-simple-sketch-switch-between-relay1-and-2-every-4-seconds
- Github Project Page: https://github.com/muffsy/relayboard
The ESP32 module used for this project is the one called ESP32s NodeMCU. It's got 2x19 pins, no pin labels on the top, and a white bottom side with the text "NodeMCU ESP-32S v1.1"
The ESP32 development kit has a CP2102 USB to UART bridge, drivers are available from Silicon Labs:
Information on how to program the ESP32 using the Arduino IDE is available from Espressif:
Espressif's "IoT Development Framework" IDF/SDK is available here, along with a lot more information: