so ive been sitting on this idea for a while now and finally starting to actually do something about it. i have an old CDE rotator that works fine mechanically but the controller box is pretty beat up and the meter needle is sticky so half the time i dont really know where the beam is pointing. instead of buying a new controller i started thinking why not just build something around an arduino and a couple of hall effect sensors or maybe a pot on the rotator shaft.

the basic idea is to use an arduino mega (i have one sitting in a drawer doing nothing) to read the position, display it on a small LCD, and eventually tie it into my logging software through a serial interface so it can autotrack based on the DX station heading. ive seen a couple of projects online that do parts of this but nothing that quite matches what i want to do and a lot of them seem abandoned or the links to the code are dead.

anyone here actually built something like this from scratch or even modified an existing design? im decent with the arduino stuff, done a few other projects, but the part im less sure about is the motor drive side — the rotator uses a fairly chunky AC motor and i want to make sure i handle that correctly and dont fry anything. any pointers appreciated

yeah ive done almost exactly this with a Yaesu G-450A a few years back. used an Arduino Uno at first then swapped to a Mega when i needed more pins for a second display. the position reading is easy if your rotator already has a pot — just tap off it with a voltage divider and feed it to an analog input, took me like 20 minutes to get that part working reliably.

the motor drive part is where you need to be careful. i did NOT try to switch the AC motor directly with any Arduino output, thats just asking for smoke. i used a pair of solid state relays rated well above the motor's actual draw, like 25A SSRs for a motor that pulls maybe 3-4A, because i wanted plenty of headroom and SSRs are cheap anyway. the Arduino just triggers the SSR coil side which is low voltage DC and everything stays isolated. worked great, been running it for probably 3 years now with no issues. i can dig up my sketch if you want, its kind of messy but it works

theres a project called "rotctld" that might be worth looking at for the software side, its part of the hamlib package and a lot of logging programs can talk to it natively including N1MM and Log4OM. if your arduino presents itself as a serial device and speaks the right protocol you can get computer control working without writing custom integration code for every program. just something to keep in mind before you go too deep designing a proprietary serial interface