Welcome to RF Current, a weekly electronic newsletter focusing on Broadcast technical and F.C.C. related issues. This newsletter is part of The RF Page @ www.transmitter.com, a web site devoted to TV Broadcast RF engineering. For more information see the What is... guide to the R.F. Page site.
This page contains stories from RF Current issues published in July 1997. Links referenced in the articles were current when published but by this time may have changed. If you find a bad link, try connecting to the home page of the publication or company and look for an archive of past articles. If you find a changed link, I'd appreciate it if you'd let me know by dropping me a note indicating the new location at firstname.lastname@example.org.
July 28 - Issue 79 Final
- INDUSTRY - Judge Awards COMARK Up to $18M In Harris
Patent Suit (July 24)
- COMARK Communications released news late Thursday that a
Federal judge in Philadelphia affirmed an earlier jury
finding that Harris Corporation's Broadcast Division
willfully infringed on COMARK's patent for its Aural
Carrier Corrector. As reported in the April
28th RF Current, the jury awarded COMARK $7.7
million. Now, according to the release carried on
Business Wire, the judge doubled the judgement against
Harris to $15.4 million because the infringement was
"knowing and intentional". In addition, the
judge ordered Harris to pay prejudgement interest of
$745,000 and granted a request from COMARK for
reimbursement of its attorneys' fees, which COMARK
estimated at $2.6 million. See the COMARK
Press Release for more information.
28th RF Current also reported on Harris' response to
the original jury verdict. In that response, Richard
Ballantyne, Harris vice president and general counsel,
said Harris would appeal the ruling to the Federal Court
of Appeals if necessary. Harris' response to today's
ruling wasn't available as this was written but will be
reported in RF Current as soon as it becomes
- FCC Releases Report And Order on Sky Station 40 GHz.
Application (July 23)
- Today the FCC posted its Second
Report and Order (FCC97153) on amending parts 2, 15
and 97 of the Commission's Rules to Permit Use of Radio
Frequencies Above 40 GHz. for New Radio Applications,
International Harmonization of Frequency Bands Above 40
GHz. and the Petition of Sky Station International, Inc.
for Amendment of the Commission's Rules to Establish
Requirements for a Global Stratospheric
Telecommunications Service in the 47.2 - 47.5 GHz. and
47.9 - 48.2 GHz. Frequency Bands.
While the Report and Order contains information and
decisions useful to other applicants wishing to establish
communications systems in the bands above 40 GHz., the
core of this document is its descriptions of the Sky
Station global wireless telecommunications service. RF
Current outlined the Sky Station system in the May
12th issue. This Order provide more details on the
service, called the Global Stratospheric
Telecommunications Service or GSTS, which is based on a
network of platforms in the stratosphere, kept aloft by
hydrogen or helium elements about 18 miles above the
earth and propelled by Corona Ion Engines that use the
surrounding atmosphere and the sun as a fuel source.
The system is designed to provide data, voice and video
communications at a 64 kbps. data rate to small personal
receivers or PC cards. The system would also provide
wireless Internet access. Lasers would link the
stratospheric platforms to each other.
USSB was concerned that the Sky Stations would interfere
with reception of DBS-TV satellites. The FCC decided to
defer USSB request that the Commission accept a service
rule requirement that would protect DBS-TV from Sky
Station interference. The FCC said it would consider the
requested restriction when it considers the need for
other use restrictions "to ensure the performance of
the authorized services under appropriate service
HCI (Hughes Communications, Inc.) and Motorola argued
that there are many open technical, financial and safety
concerns that must be addressed before the FCC acts on
this. In particular, HCI and Motorola argued that
"there are significant public safety risks posed by
the use and size of the platforms, their untested
technology, and their location over major metropolitan
areas and in aircraft flight paths."
text of this Report and Order presents an almost
sci-fi version of future telecommunications. It makes
- FCC Preempts Meade Kansas Satellite Dish Ordinance
- After declining to preempt several ordinances (see RF Current for July 14), the FCC
today granted a Petition for Declaratory Ruling filed by
Star Lambert and the Satellite Broadcasting and
Communications Association of America.
The FCC Ruling found problems with the city's permit and
fee requirements, the penalties for non-compliance and
the city's antenna location requirements. One interesting
aspect of this case is that although the city repealed
the ordinance prior to the FCC's decision and replaced it
with another one, the FCC rejected Meade's contention
that the Petition is now moot. The FCC instead based its
decision on the new ordinance.
This case makes interesting reading for anyone interested
in the battle between local governments and the FCC over
the right to regulate over the air reception devices.
Full details are available in the Memorandum
Opinion and Order (DA971554).
- FCC Acts on Satellite Applications in 2 and 40 GHz.
bands (July 22)
- The FCC's International Bureau announced in a Public
Notice (DA971551) that it found the application by
Motorola for its M-Star system was acceptable for filing.
The M-Star system is a global network of 72
non-geostationary satellites. Uplinks will operate in the
47.2 to 50.2 GHz. band and the downlinks (satellite to
earth) will operate in the 37.5 to 40.5 GHz. band.
Intersatellite links will operate between 59 and 64 GHz.
and 65.0 to 71.0 GHz. Up to six tracking, telemetry and
control sites will use the uplink bands. The service will
provide voice and data services at data rates ranging
from 2.048 Mbps. to 51.84 Mbps using earth stations with
antenna aperture sizes ranging from 0.66 to 1.5 meters.
The FCC invited filings by new applications for satellite
systems in the 40 GHz. band. More information is
available in the Public
In another action, the International Bureau established a
cut-off for additional space station applications in the
2 GHz. band. Public
Notice (DA971550) invited
"(1) amendments to existing applications and
(2) new applications for authority to construct,
launch and operate U.S.-licensed geostationary and
non-geostationary satellite system and (3) letters of
intent to use non-U.S. licensed space stations in
providing mobile satellite service to, from and
within the United States to be considered in the
First 2 GHz. Band Processing Round in accordance with
the Commission's 2 GHz. Allocation Order released
March 14, 1997."
The frequency bands allocated for the service are 1990
to 2025 GHz. and 2165-2200 MHz. Refer to the Public
Notice for more details.
- OTHER Items of Interest
July 21 - Issue 78 Final
- TV - Larcan-TTC Approves Merger with Larcan Inc. (July
- Larcan-TTC, based in Louisville, Colorado, announced it
had approved a definitive merger agreement with Canadian
based Larcan, Inc., currently a 78.4 percent shareholder.
If approved by Larcan-TTC shareholders, the company will
become a wholly owned subsidiary of Larcan, Inc.
For more information on Larcan, see its web site at http://www.larcan.com.
Information on Larcan's parent company, LeBlanc and
Royle, is available at http://www.leblanc-group.com.
- FCC Experimental Actions (July 18)
- The FCC has released its list of experimental application
granted in June. Interesting licenses include WA2XLT, to
Tracor Aerospace Electronic Systems, Inc. for operation
on 74.7, 140, 225, 450 and 959.995 MHz. to do radiation
hazard and antenna tests under a Government contract. The
station will be located in Lansdale, PA. Radian
International was granted three licenses to operate wind
profiler radars on 915 MHz. in Temecula, Riverside and
Palm Springs California.
A complete listing of all experimental applications
granted in June is available from the FCC in Public
- FCC Moves To Allow Non-U.S. Satellites to Serve the
U.S. (July 17)
- The FCC has released a "Further Notice of Proposed
Rulemaking" seeking additional comment on a
framework to allow satellites licensed by other countries
to provide service in the United States. The News Release
noted that the FCC would retain its proposed ECO-Sat
tests for satellite licensed by non-World Trade
Organization members, for intergovernmental organizations
and for services such as direct-to-home TV,
direct-broadcast satellite TV and digital audio radio.
More information is available in the FCC News
Release NRIN7026. The full text of of the Further
Notice of Proposed Rule Making is available in the
International Bureau's Notices directory under FCC97252
- SPACE - Human Planetary Travel Will Require New
Technologies (July 15)
- A report from the Natonal Research Council said today's
technologies would not be able to sustain crews
affordably on missons beyond Earth's orbit. Even though
there are no immediate plans for such exploration, that
situation is likely to change in the next two decades.
The report recommended focusing programs on key
priorities such as a self-contained life support system
and spacesuits designed for use on planet surfaces.
See the Press
Release from the National Research Council for more
information on this NASA funded study.
- OTHER Items of Interest
July 14 - Issue 77 Final
- FCC Proposes Reallocating TV Channels 60-69 To Other
Services (July 9)
- The FCC today released a Notice
of Proposed Rulemaking that would allocate 24 MHz. of
spectrum now used by TV channels 63, 64, 68 and 69
(764-776 MHz. and 791-806 MHz.) for use by Public Safety
radio systems. The remaining 36 MHz. would be allocated
to fixed, mobile and possibly broadcasting. Existing full
power stations would be protected from interference,
although the criteria for this protection was not
specified. While the FCC welcomed comments on how to
mitigate the impact on LPTV and translator stations, the
NPRM also states: "We emphasize, however, that any
accommodation of low power operations should not impede
public safety use of the spectrum nor reduce the
opportunity for other services to use this
spectrum." One alternative suggested was to defer
allocation of some of this spectrum until after the DTV
transition period ends in 2006.
For more details, see the FCC's Web Page on this issue at
For information on public safety radio spectrum
requirements, see the Public Safety
Wireless Advisory Committee page.
- FCC Declines to Preempt Local Zoning Regulation for
Some Sat Dishes (July 9)
- Today the FCC released several Memorandum and Order
relating to requests that it preempt local governments
and allow certain satellite dish installations. The FCC
declined a request from Hughes Network System that it
preempt the zoning ordinances of Coconut Creek and Coral
Gables Florida and allow VSAT dishes on the roof tops of
some service stations. The reason given was that Hughes
had not shown that it had "exhausted all local
administrative remedies". Full details are available
Bureau Order DA971365.
In another case, the FCC declined a request from
TerraStar, Inc. to have its new C-band satellite dish
system covered under the Commission's rules on
over-the-air reception devices. The TerraStar system is
interesting in that instead of using the conventional two
to three meter dish for C band reception, it instead uses
a linear array of three adjacent parabolic dishes, each
0.53 meters in size. The total length is greater than the
one meter allowed dishes to qualify under the
over-the-air reception devices laws. While the FCC
declined this request, it said it would consider
instituting a Notice of Proposed Rulemaking to deal with
these "significant issues." Full details are in
Bureau Order DA971364.
The FCC's collection of decisions in several satellite
receive dish cases were released on the Internet
Wednesday. To find additional cases, check http://www.fcc.gov/Bureaus/International/Orders/1997/
and look at the files surrounding the Orders listed
- OTHER Items of Interest
July 7 - Issue 76 Final
- CONSUMER - AITECH Introduces 2.4 GHz. Wireless Link
for the Home (July 7)
- AITECH announced its
new PC/TV Airlink, a device which connects to a PC, scan
converts the video, then transmits it to a receiver
connected to a TV set up to 300 feet away (100 feet
through obstructions). In addition to providing a
wireless link from the PC's video monitor and sound board
to the TV, it also comes with a wireless keyboard / mouse
that uses an IR link to communicate with the set-top
receiver box and back to the computer. AITECH says the
keyboard / mouse combination was designed for laptop use
while sitting on a couch or easy chair. Although designed
for the home, don't be surprised if this unit turns up in
some business settings. The 2.4 GHz. transmitter has a
PLL synthesizer with four channels. See the AITECH
PC/TV Airlink page for more information. Suggested
retail price is $399.
- SCIENCE - Pathfinder Lands On Mars (July 6)
- For the first time in over twenty years, a spacecraft
from Earth has landed on Mars. As one would expect, the
images are sharper and coming in much faster than the
first pictures from Viking. NASA has teamed up with
Silicon Graphics, Compuserve, Sun Microsystems and other
Internet servers around the world to cover the Mars
landing and exploration. Choose the server nearest you at
You'll find updates seem to run about half a day behind
event. Want more pictures? Check out the Imager For Mars
Pathfinder (IMP) Page. (Original story dated July 3,
Revised July 6)
- FCC Considers Reallocation Of TV Channels 60-69 At
Open Meeting (July 2)
- According to the Agenda.released
Thursday, the Federal Communications Comission will
consider the reallocation of television channels 60-69,
the 746 to 806 MHz. band, at its open meeting Wednesday,
July 9th. Recent bills introduced in Congress require the
Commission to allocate 24 MHz. of spectrum as soon as
possible for public safety use. See Senate
Bill 705, introduced by Senator McCain.
The audio portion of the meeting, scheduled to start at
9:30 AM EDT, can be heard via the Internet, using
RealAudio. Visit http://www.fcc.gov/realaudio/
- FCC OET RELEASES BULLETIN 69 ON TV COVERAGE EVALUATION
- The long wait is over. The FCC's Office of Engineering
and Technology released OET Bulletin 69, titled Longley-Rice
Methodology for Evaluating TV Coverage and Interference.
Longley-Rice is a very flexible program designed to cover
a wide range of applications and locations. OET-69
provides the parameters needed to provide the results
needed for FCC TV broadcast applications under the new
rules released in the FCC's 6th Report and Order on DTV.
(See the April
21, 1997 RF Current).
OET-69 is available from the FCC Office of Engineering
and Technology Web Site in WordPerfect
OET-69 doesn't address all the issues put forth by Dr.
Oded Bendov in his paper Understanding
the Requirements for DTV Construction Permit Application
or the Petition
for Reconsideration filed by Hammett and Edison
(Acrobat File - 508k). The outline at the front of the
Bulletin, for example, mentions "grid cells over
water" but the text doesn't contain any information
on this. In spite of these limitations, OET-69 provides
much of the key information missing in the FCC's 5th and
6th Report and Order on DTV. Resolution of some of the
issues raised in the two papers mentioned earlier will
likely require higher level approval at the FCC. OET
should be commended on their efforts to clearly define a
The FCC in general and OET in particular should be
complimented on their decision to make the Fortran source
code of the FCC's computer program for DTV coverage and
interference analysis available on the FCC Internet site,
along with a database of DTV antenna patterns. Neither of
these were available July 2nd, when OET-69 was released.
The Longley-Rice program or, more accurately, the
Irregular Terrain Model, Version 1.22, has been available
on the Internet for sometime. You can find the source
code in Fortran along with documentation and a very
limited capability DOS program at http://elbert.its.bldrdoc.gov/itm.html.
I'll have more on Longley-Rice in my August 1997 RF
Column in TV Technology magazine.
- WIRELESS - Warp Drive Networks to Use UHF LPTV Channel
For Internet Service (July 2)
- According to a story on Business Wire today, Warp Drive
Networks has been granted permission by the FCC to use a
transmitter operating in the low power UHF TV spectrum to
transmit its wireless Internet Access Service. The
service will provide coverage in Silicon Valley. The same
company will also use MMDS frequencies, in a cellular
configuration, to provide coverage in the Seattle market.
The LPTV transmitter provides the path from the Internet
to the user. The return path will still require another
Internet connection, such as a dial up phone line. This
is similar to how Hughes DirectPC service currently
operates. Monthly fees will start at $150 / month for
128k of bandwidth.
More details are available on the FAQ
page at Warp
Drive Networks home page. While the manufacturer of
the equipment wasn't mentioned, both ITS Corporation and EMCEE showed wireless
Internet solutions at the recent WCA convention in
California and both sell UHF LPTV transmitters and MMDS
equipment. Use the links in the previous sentence to
visit their home pages.
- OTHER Items of Interest
Other Issues Available:
1995 and 1996
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Last modified July 28, 1997 by Doug Lung email@example.com
Copyright © 1997 H. Douglas Lung