This is a mod to the old IC-22S 2MFM ham radio. It removes the channel switch and diode matrix then replaces the with an Arduino, OLED display and rotary encoder.
All this is easily reversible too.
The old channel switch panel is removed, as is the switch with attached diode matrix board.
Then this is installed in its place.

Note, as of the time of posting, this is still under development.
See http://www.sadarc.org/xenforo/upload/index.php?threads/ic22s-arduinoized.275/ for the ongoing design progress.
The OLED display pictures demonstrate simplex RX, simplex TX, duplex and duplex reverse.
As seen, on TX, the foreground and background reverses. On a duplex channel, holding in the encoder button selects reverse. The frequencies, mode and CTCSS tones are held in tables and the encoder selects each channel defined in the tables.
Sample code is on the SADARC forum for both I2C driven and direct from the Arduino Nano ports. Check the forum for info as to the success of the project.

edit: 20230316 Added a second front that has provisions for two push buttons.
And there is a picture of the wiring too. A couple of resistors can fit in the cutout between the push buttons and wired to suit. For the IC22S, the wires will best be laid flat, not straight up on pins.

Wombot

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