Baofengs seem like a good choice for inexpensive APRS etc. However I’ve always run into an issue which I’ve never found a solution for – the rig keys up, but doesn’t unkey again. Not much good.
I just came across this page, which claims to solve it. Summary: put a 2.2k resistor in series with the PTT line.
No explanation given as to why that fixes it. I will try this out…