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Old September 17th 08, 02:57 AM posted to rec.radio.amateur.antenna
Sal M. Onella Sal M. Onella is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 442
Default Chart of HDTV freqs?


"Cecil Moore" wrote in message
...
Sal M. Onella wrote:
By the old TASO standards, you need over 40 dB s/n to get a nice

picture,
which requires a lot more peak RF power. By comparison, the digital

signal
needs only about 17 dB s/n.


What happens at a 12 dB s/n for both? That's probably
what happened here during Hurricane Ike.
--
73, Cecil http://www.w5dxp.com


Digital: No lock and no indication of trying to lock (which is provided on
some receivers)

Analog: Recognizable signal, possibly with sound, probably with no color
and so much snow as to be unwatchable.

For the analog experiance, I am relying on bench tests I did with a TV
servicing generator. For baseline, I advanced the RF amplitude just to the
point where I had a snow-free picture. Next, I added 10 dB attenuators and
noted the results with each addition.

One: observable snow, no big deal
Two: Objectionable snow, this ain't good
Three: horrible snow, I can't watch this.
Four: Is there even a picture?