Got my K1 cables for the #DigiRig today, meaning I should be able to have an audio I/F to most HTs. (And if they're RS-232 serial, I can program them too.) So I just did some low-power APRS testing... and sure enough, plug in the GT-5R and my 878 was decoding packets from it.
Only one issue: the AnyTone 878 doesn't PTT in the same way, apparently, so that's not doing anything. I guess that means this cable is Baofeng only... but you know, the GT-5R has "enough" filtering (certainly more than the UV-5R) and a portable APRS station is a portable APRS station. I think I can work with that.
I'm not saying "drill a hole through your #Baofeng" but what I am saying is, I widened the mic hole with a tiny hand drill and my voice does not sound nearly so muffled... if you do this, you could drill through your mic... which would not be good... also dust and things... and no more warranty... on your Baofeng #UV5r etc
Edit: Actually, I did this to two Baofengs and both sound better on the other end now... wind and plosives are an issue... but I side-mic anyway