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Referring to:
http://en.wikipedia.org/wiki/TV/FM_DX

And referring to:
Has anyone attempted to 'moonbounce' or EME ATSC UHF band TV signals, in the 
UHF band allocation?
It might make a nice publicity stunt for the TV station involved.
What such a test could accomplish:
1. Find out if ASTC error correction can survive EME, enough that is to get 
a station ID.
2. Find out what 'emergency utility' such a communication system might 
possess.
3. As a propagation experiment.
4. As a test of a radio astronomy network.
5. A similar test of DVB-T would also be welcome.
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In my "experiment", a special broadcasting antenna would point straight at 
the moon.
This would eliminate the distance requirement, albeit I would prefer a 
1500-2000 kms separation between the station and say Airecebo or Canberra.

"DC" components to look for:
There is a select part of the ATSC signal that goes to '0' for a select 
number of bytes.
This causes a spike in the ATSC waveform, allowing decoders to lock on the 
DC component qualities of the signal at that point.
It is not the same thing as sync pulses, but this DC component of the signal 
could make up for trying to detect a carrier wave (that may be eliminated 
due to 200 db path loss).
ATSC signals may be up to 200 Hz (400 Hz?) offset from NTSC carriers, so as 
to avoid 'beat' interference.
This offset will be abolished when NTSC transmissions cease -- unless there 
is an ancillary requirement to have the offset.

| While not yet confirmed, the 305-metre Arecibo radio telescope may be
| capable of receiving weak viewable EME television pictures. Based on
| mathematical calculations assuming 60 dB antenna gain, FM broadcast EME
| reception may also be possible using the Arecibo dish antenna.

Given it's narrow viewing angles, this does limit the range of earth
stations it could pick up this way.

Since the Arecibo radiation pattern points nearly upwards, the Moon
must be close to zenith.

OTOH, due to the UHF TV transmitter radiation pattern, the Moon would
have to be close to the horizon when looking from the transmitter
site. To satisfy both these requirements, the transmitter would have
to be at an distance of 9000 - 10000 km from Puerto Rico. Not too many
ATSC transmitters within that area :-).