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DTV signals creating interference to SF & LA P/S systems

Started by Gregg Lengling, Monday May 10, 2004, 06:18:27 AM

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Gregg Lengling

LAND MOBILE COMMUNICATIONS COUNCIL
9484 Westpark Dr., Ste. 630
McLean, VA 22102


May 4, 2004


John B. Muleta, Chief
Wireless Telecommunications Bureau
Federal Communications Commission
445 12' Street. S.W Rm. 3-C252
Washington. DC 20554


RE: INTERFERENCE PROBLEM KSEE-DT (CH 16)/LAND MOBILE
       FACILITIES IN SAN FRANCISCO/LOS ANGELES


Dear Mr. Muleta:


The Land Mobile Communications Council ("LM.CC') is writing to
express its very serious concern about the destructive interference
being caused to primary land mobile systems in the San Francisco
and Los Angeles markets by a new co-channel digital television
station, KSEE-DT, operated by Granite Broadcasting Corporation in
the Fresno. CA area. (1)  The LMCC urges the Federal Communications
Commission ("FCC") to take prompt action to eliminate this ongoing
interference to land mobile facilities while a long-term solution to the
problem is identified and implemented.

Private land mobile radio ("PLMR") users in both San Francisco and
Los Angeles an authorized for primary, protected use of TV Channel
16. The San Francisco allocation was included in the original land
mobile/TV sharing proceeding more than thirty years ago and licensees
have made intensive use of this spectrum since then. (2) Subsequently,
in 1996. the FCC made a special allocation of this same channel for
public safety use in Los Angeles (3). The Channel 16 frequencies in San
Francisco we used by a variety of public safety, private internal and
commercial systems. In Los Angeles, the channels handle virtually all
radio communications for the Los Angeles County Sheriff's Department.

PLMR licensees in both areas had operated without interference since
these allocations were made. (4)

In May 2003, KSEE-DT began broadcasting digitally. Almost immediately,
land mobile users in both markets began experiencing destructive
interference. It has been determined, and KSEE-DT does not dispute,
that the interference is being caused by its facility. The station is
located
more than 250 km from the centers of both San Francisco and Los Angeles
and, therefore, satisfies the separation requirement established in FCC
Rule Section 73.623(e). However, that rule does not consider the antenna
height or power level of the broadcast station. but relies entirely on a
distance separation. KSEE-DT operates from Meadow Lakes, one of the
higher peaks on the eastern side of the San Joaquin Valley, an area of
recognized anomalous propagation characteristics. (5) The result is
KSEE-DT's presumably unintentional but, nevertheless, intractable
interference to public safety and other important land mobile operations.
(6)

It has been almost three months since the FCC was formally notified of the
existence of ongoing destructive interference to numerous, primary land
mobile
operations in the San Francisco area. The FCC has been on notice about
interference to critical public safety operations in Los Angeles for almost
two
months. No action has yet been taken to the best of the land mobile
community's
knowledge, and there is no indication that this matter will be resolved
satisfactorily
without prompt Commission intervention.

LMCC urges the Commission to delay no longer. Appropriate steps should be
taken immediately to eliminate the current interference problem while a
permanent
solution to this situation is identified and implemented.

Sincerely,

Jim Pakla
President


Footnotes:

(1) See Request for Issuance of Cease and Desist Order, Station KSEE -
Channel
16 DTV, Fresno, CA filed by Champion Communication Services, Inc. (filed
Feb. 3, 2004)
("Champion Request"); Interference Complaint and Petition filed by the
County of
Los Angeles (filed March 5. 2004) ("County Petition").
(2) Second Report and Order, Docket No. 18261, 22 RR 2d 1691 (1971)
("Docket No. 18261"),
(3) Amendment of Parts 2, 73 and 90 of the Commission's Rules and
Regulations
to Allocate Additional Channels in the Band 470-512 MHz for Public Safety.
Gen. Docket
No. 84-902, Report and Order, 59 RR 2d 910 (1986).
(4) The land mobile/television sharing arrangement authorized pursuant to
Docket
No.19261 has a long and successful history. Thousands of PLMR facilities
have
operated without receiving interference from or causing interference to
co-channel
or adjacent channel broadcast stations for more than three decades in eleven
major
urban areas, LMCC believes that the instant situation is unique, specific to
the
geographic area involved and even, perhaps, to the particular transmitter
site selected
by KSEE-DT. LMCC has every expectation that additional land mobile shared
use of
this valuable and currently underutilized spectrum could be implemented
without
interference problems. See ET Docket No. 02-3,80, Comments of the LMCC filed
Apr. 17, 2003
(5) See, e.g.,. 47 C.F.R. ยง 90.621 (b) Table 1.
(6) KSEE and the County of Los Angeles cooperated in field testing that
identified
KSEE as the source of the Sheriff's interference and quantified the impact
of its
operation. However, those tests did not result in KSEE taking any steps to
eliminate
the interference problem See County Petition at up. 2.


Source: http://www.lmcc.org/filings.html
Gregg R. Lengling, W9DHI
Living the life with a 65" Aquos
glengling at milwaukeehdtv dot org  {fart}