[Jeffhs]

I watched the local TV stations in Cleveland (channels 3, 5 and 8 at the time, '60s-'70s) sign on and sign off, back when TV stations still left the air at one or 2 a.m. for three or four hours, signing on again at six a.m. the following morning (long before today's 24-hour television and infomercials).

Channel 8 in Cleveland, the CBS station at the time, would stay on the air well past midnight on Friday nights with horror movies. The other two network stations would leave the air shortly after the last network program ended; the stations would show a couple of local religious programs (I remember "Credo" on channel 3), and then the sign off announcement. After that, snow and static until the stations returned to the air some time around six a.m.

I'll never forget one morning back in the '70s when I had my TV on at 5:30 a.m. or thereabouts, before channel 5 in Cleveland signed on. I didn't have any special kind of antenna on my set, just rabbit ears, but I remember seeing a reasonably good picture from the then-NBC affiliate in Flint, Michigan, WNEM-TV on channel 5. Of course, that image went away in a hurry once Cleveland's channel 5 signed on.

Even though TV stations don't sign off at night anymore, there are times when some stations interrupt their programming briefly after midnight. I get a PBS station on my cable from a town about 30 miles southwest of here; the station normally runs 24 hours a day, but last night at about 2:00 a.m. or thereabouts, I saw a color bar test chart (not a round test pattern) with a small square bouncing around on the screen, and a black box in the center of the pattern, inside which was "xxxx Columbus" (I couldn't make out the word ahead of the city name, but I think it may have been a network or station ownership ID).