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                      THE CGC COMMUNICATOR

                            CGC #439

                     Tuesday, March 13, 2001

                 Robert F. Gonsett, W6VR, Editor

     Copyright 2001, Communications General Corporation (CGC)

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  NTSC + HDTV SIGNALS IN A STANDARD TV CHANNEL?  NOT SO FAST!

  The story carried in EE Times and cited in the last CGC
Communicator ("The Department of Energy's Los Alamos National
Laboratory has announced an encoding algorithm that squeezes a
high-definition television signal into the existing 6 MHz NTSC
channel....") greatly overstates the case.  Jerry Plemmons,
Systems Engineering Manager for Harris Broadcast Systems,
writes as follows:

  "The response to the Los Alamos Labs story was swift:

  "File this in the "too good to be true" department....a
variation on the Los Alamos Labs story was posted on the PBS
intranet a few days ago, quickly followed by a rebuttal posting
quoting Dale Cripps, Publisher of HDTV Magazine.

  "The news release from Los Alamos Labs that Howard sent out
earlier today caused me to dash to the phone and talk to George
Nikel, the engineer at Los Alamos who had devised the system.
George quickly admitted that he is an outsider to broadcasting
and was just "tinkering around" with some ideas formed when
making a transmission system for remotely monitoring nuclear
test shots, which are no longer conducted there.  He had already
talked with Bruce Franca from the FCC's technical arm, and Mark
Richer, Executive Director of the Advanced Television Systems
Committee (ATSC), and each politely told him that there would
be little-to-NO interest in his system at this stage of the game.

  "But would the technology work?  Only with highly disagreeable
side effects (gray bars in letter box, very low color bit rate,
etc.).  Again, no testing had been done--just lab-based
theoretical calculations.  The system works only for the
environment and application in which it was singularly designed,
but it is nowhere near to the sophistication of the early single-
channel compatible works done by Fukinuki in Japan, or that done
by the NBC/Sarnoff combine in the mid 80s, when NBC sought to
construct a EDTV-quality widescreen system called ACTV-1.
Those systems were abandoned for the solution we embrace now.

  "Mr. Nikel said he had no peer review of his system and from
what he has now learned he realizes that it is going absolutely
nowhere.  We must wholeheartedly agree with his conclusion.  The
news-release, however, has reverberated around the nation and
we were contacted by the Associated Press, who was busily writing
a story on it.  Don't be confused.  There is nothing to it.  You
just have to wonder how Los Alamos could put out a statement
like that!"

  dbiondi@broadcast.net  03/09/01 12:08AM

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  SOME RADARS DO IN FACT EMIT SIGNALS IN THE C-BAND

  Regarding the article on radar interference and the second
writer who had never found the radar to be at fault (CGC #438),
we have in fact found radar spilling into the 3.7-4.2 GHz range
here in San Diego County.

  Several years ago, Navy ship radar was causing severe
interference to Daniel's Cable, Time Warner Cable and Cox North
County headends, along with many San Diego area broadcasters.
In a meeting with the Navy, FCC, broadcast and cable engineers,
Don Williams of Daniel's Cable showed video tapes of a spectrum
analyzer showing radar signals operating below 4.2 GHz.

  The Navy corrected this problem and also developed a plan to
reduce power as the ships came into the area to help prevent
overloading LNBs.

  Dennis Younker, Cox Cable, San Diego

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  ADDRESS FOR THE KCET/MT.WILSON/FOREST SERVICE MEETING

  In case anyone needs the street address for this coming
Monday's meeting with Forest Service staff (see CGC #438),
KCET is located at 4401 Sunset Blvd., Los Angeles.

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