so ive been messing around with an arduino mega for the past few weeks trying to get it to handle antenna switching based on what band my radio is on. the radio is a ts-590sg and it outputs band data on the accessory port which is nice. got the basic logic working where it reads the voltage levels and drives some relays but the timing is all messed up — like sometimes it switches before the radio has actually settled on the new frequency and i get this ugly pop through the audio.

im using a 4 relay module i grabbed off amazon, nothing fancy, and just standard digitalWrite stuff in the loop. wondering if anyone has done something similar and whether adding some debounce delay actually helped or if theres a smarter way to do it. ive seen people mention interrupts but honestly my interrupt experience is pretty limited and i dont want to overcomplicate this if a simple delay(50) or whatever would just fix it.

also considering moving this over to a raspberry pi zero at some point just because it would be easier to add a little web interface for remote monitoring but not sure if the latency on the pi would make the timing even worse. any thoughts from people who have actually built stuff like this would be appreciated

yeah i did almost exactly this with an ic-7300 about a year ago. the band data voltage thing is straightforward enough but the timing issue you're describing is real and a simple delay fixed it for me — i think i landed on around 80ms before triggering the relay and that was enough for the rig to finish its internal switching. the pop was gone after that. not elegant but it works and the arduino doesnt care about wasting 80ms sitting there.

one thing i'd warn you about with the pi zero is that linux isnt real-time so if your timing ever needs to be really tight you can get weird jitter. for antenna switching it's probably fine since youre not talking microsecond precision, but i tried to use a pi for ptt keying once and the latency was all over the place. for a web interface and monitoring though the pi is way better than trying to bolt ethernet onto an arduino. maybe keep the arduino doing the actual relay switching and have the pi just watching and logging — have them talk over serial or i2c. thats how my current setup works actually and its pretty solid.

dont overthink the interrupt thing for this use case honestly. if the band data is just a voltage level that changes and stays put, polling it in your loop with a delay is totally fine. interrupts shine when youre catching fast pulses or need sub-millisecond response and antenna switching just isnt that. id just throw a delay in there and call it done.