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RE: Question about TV on Ham satellite

In reply to questions from Howard - G6LVB, Gunther - W8GSM asked:
> Not real sure what you are trying to do here, but you talked about 18MHz
of bandwidth required for FM  TV...
> Commercial NTSC TV takes 6 MHZ of bandwidth for one signal.

6 MHz is for AM video (standard TV broadcast here in the USA).

Narrow band FM video is about 17 MHz wide (depends on audio sub-carriers
mainly).  This is commonly used by amateurs in the low microwave bands and
is what is used by some TV remote trucks and both news and police
helicopters.  It is also used for the part 15 video links that many of us
get to listen to when trying to copy the S-band AO-40 downlink.

Wide band FM video is about 35 MHz wide and is used by amateurs in some of
the higher microwave bands, and also is (or often was) used for C-Band
satellite downlink - you know, all those big dish TVRO systems that we get
big free dishes from.  I said "or often was" in the previous sentence
because most (but not all) of the C-band satellite TV is now digital.  A
lot of the TV remote stuff is also digital and uses several other frequency
bands besides S-band.

Jim Walls - K6CCC
Mobile Radio Operations
Southern California Edison Co.
Ofc:   626-302-8515   -   PAX   28-515
FAX:   626-302-7501   -   PAX   27-501

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