> At about 1am last night, WMHT was signing off, and at the
> instant they signed off, it flipped from the test pattern to
> another PBS feed. This feed had the WMHT bug in the lower
> right as well? What is that other feed? Is it programmed to
> automatically flip to it when WMHT signs off?
This is also done at some commercial stations too, but it's pretty rare to find one that actually signs off overnights anymore. The one example that comes to mind is WKTV in Utica.
Last time I caught it, they were signing off after Conan O'Brien, not opting to carry Carson Daly over the air. Once Conan was over, they'd play their signoff thing, then play a cart explaining that programming would continue through the night only for customers of Adelphia & Time Warner Cable.
The move allows them to save some bucks by shutting down the transmitter and allowing master control to go unmanned, even if just for a few hours.
The one "kinda neat" thing about letting the NBC network feed go unmanned all night, is when Carson or the reruns of the Tonight Show hit commercial breaks that include time for local spots. It's kind of surprising, but NBC doesn't fill the time with PSA's or promos like most other broadcast networks.
Instead, during local spot breaks, the network runs different animations of the NBC peacock logo. It's nothing extravagant, but unless the master control op at your local affiliate screws up big time, it's something viewers normally don't see on the air.
