In October 2018 I started using a Comtech 23cm transmitter for my ATV operations. Rather than use the 8-way dip switches to tune the transmitter, I decided to work on a project to develop a rotary LCD tuner using an Arduino Uno as the micro-controller. This article shows how I did it, including the code.
For 23cm Amateur TeleVision (ATV) I am using a Comtech 23cm transmitter powered by a 13.8V power supply.
This article tells why and how I replaced the voltage regulator.