I got lucky recently and found a few TBCs on Marketplace in Vietnam right as they were posted. The seller works for datavideo and seems to find old stuff at their distribution warehouse from time to time. Everything I bought was in the original box and seemed to be unused.

There was a TBC 1000 which works just fine, but I bought 2 TV One 1T-TBC-GLs and they both seem to have the same issue. I can't get any signal to come through using the S-Video or Composite IN/Out ports. I can get picture when using the Genlock IN and the Loop as OUT, but I'm not sure if the device is actually doing anything. For my purposes I was interested in them as a way to stabilize signals when working with circuit bent gear and feeding a digital projector or capturing. When testing the TBC 1000 I could tell it was doing it's job when feeding a signal to my computer, but with the TBC GLs there seems to be no difference. Also the buttons work in the sense that you can move the lit up part to difference features, but again, they don't seem to have affect in controlling color, brightness, etc when pressed.

Even though these things seem to be new, I guess they've been sitting on a shelf in Vietnam for god knows how long. Any possible suggestions? If not, would it be worth it to throw them on Ebay for parts or repair? I don't know much about these ones or how sought after they are. I know they're known to be not great but I suppose any of these TBCs are hard to track down these days?