Richard Fry wrote:

Before calling this reality absurd, consider that a television station
transmits a video signal in/on an RF channel. The demodulated video
waveform in the TV receiver will be identical to the baseband video
signal applied to the TV tx -- including its DC components (subject to
any distortions along the transmission path).

If it wasn't ~ identical, a TV set could never "fade to black" when the
original image did, and low-luminance colors such as blue, red, brown
etc would be impossible to reproduce with their original chromaticity.

RF (ex-RCA Field Engineer, and installer of
hundreds of TV color studio and film cameras)

You perhaps never installed a receiver. Without its DC restorer circuit,
the problems you mention do indeed exist. In a black-and-white set, a
large white area will cause everything else to go black, to maintain a
zero average. But the DC information is transmitted as a level
difference between the sync tip and the "porches". At the receiver (as I
mentioned in another post), this voltage *difference* is turned into a
DC value. No DC is transmitted.

Surely a little bit of thought will establish why direct transmission of
DC isn't possible beyond the range of a static field.

Roy Lewallen, W7EL