Thanks to K6STI, K6JRF, and many others for sharing what they know about the XDR! I'm just a hobbyist trying to add something useful to the pool of XDR knowledge and to extend their service life.
As a supporter of public radio I was happy to donate a specially-modified XDR to Eugene public radio station KRVM to help improve the quality of their rebroadcast signal in the small mountain community of Oakridge, about 40 miles from Eugene (KAVE 88.5 Oakridge). They had been using a DaySequerra broadcast-grade HD receiver in Oakridge to receive KRVM-HD1 over the air from Eugene, then rebroadcast it locally. The DaySequerra died and would have been very expensive to repair or replace, so they were using a backup analog FM receiver that couldn't get a clean signal from Eugene. I offered the Sony XDR for them to try and it works great! It has a solid lock on KRVM-HD1, which then feeds the KAVE 88.5 transmitter. That XDR has been in continuous service since August 2014.