After trying to burn sections of DVR video to TDK +R 16x / RW DVD, I remembered: how media starts life is critical.
My Funai SV2000 set top box can use plus r or dash r media, on single layer or dual layer disks. Of course, I could not erase and reuse the disks prepared as plus r in the set top box in my notebook, plus r is write once.
Sadly, preparing an RW (DVD-RAM) disk in the notebook generated a "unusable media format" message on the Funai set top box that works fine in a JVC SR-DVM700US DAT to DVD recorder set top box.
A loose video cable helped create a 2 hour video of hash on screen and hiss on the audio tracks (I had recently watched Kurosawas' 7 Samurai, and wanted to capture several costume emblem patches, so turned off the TV during recording). After re-seating cables I made a list of capabilities of the set top boxes and 6 various DVD computer drives, internal and external, to reduce gotchas.