Thanks for the link. It was Crunchy doodle's Dead Tuner fix that worked on a previous unit.
" Fix for an apparently dead 5XXX tuner:
Originally posted by Crunchy Doodle at AVS Forum here:
1) Press the power button to turn the unit off.
2) Disconnect the RF coax cable from the back of the unit.
3) Unplug the unit's power cord from the wall.
4) Reconnect the RF coax cable to the back of the unit.
5) Wait at least one minute.
6) Plug the unit's power cord back in and allow it to boot up.
7) Enjoy flawless ReplayTV operation."
This brings back the video for a matter of minutes until you press any key on the remote and it snaps off to the ReplayTV blue screen of death.
I have three units out of four down right now. When the new imaged drive arrives and is installed in the unit with the dead hard drive, I'll check the power supplies on the other two.