Hello Doug,
It sounds like you have quite a bit of RF in the shack. I have D-Star
here with no problems on an Icom 91AD. Do you do a lot of transmitting into
non-resonant antennae? Do your radios still lock up when transmitting into
an antenna that is closer to being resonant?
It all shows a severe electromagnetic incompatibility in your shack.
Check if all goes OK with dummy load, both at the HF radio and at the
tuner output.
If all goes OK with a dummy load, then you may have RF feedback (bad)
into your power line, that feeds all the faulty equipment.
It is
