Edited by: Mark Croom
Electronic Version: Leonard Charles
Electronically Distributed by Chris Cain
Contributors this month:
Tom Weeden
Chris Cain
Paul Stoffel
Neal McLain
Tom Smith
Steve Paugh
Articles Welcome!! Send correspondence to:
Chapter 24 Newsletter
34 Rustic Parkway
Madison, WI 53713-4700
or call (608) 271-1025 (home) or (608) 221-1979 (work)
or Email at mcroom@aol.com
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MEETING ANNOUNCEMENT
This month's program will be a tour of the new Madison Community
tower, formerly known as "The Candelabra". Dutch Treat dinner
and meeting at the Speedway Bar and Grill at the intersection of
County Hwy M and Mineral Point Road, across from Menards.
Candelabra location is 8559 Mineral Point Road, turn left
opposite Pleasant View Road.
Visitors and Guests are welcome at all SBE meetings.
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UPCOMING MEETINGS
Tentative Program Subjects
Wed, Jan 17, 1996
TBA
Thu, Feb 22, 1996
JVC Digital "S" or Panasonic Digital
Tue, Mar 19, 1996
WP&L Center Tour (or Milwaukee area station tour)
Wed, Apr 24, 1996
Chapter Elections and annual NAB review
Thu, May 23, 1996
TCI Cable TV Technology
Tue, Jun 18, 1996
Related technology; Internet/software support
Sat, Jul 27, 1996
3rd annual Chapter 24 Family Picnic
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CHAPTER 24 OFFICERS:
CHAIRMAN:
Paul Stoffel (WI Public TV)
W - 608-263-2175
H - 608-241-4621
F - 608-263-9763
STOFFEL@MAIL.ADMIN.WISC.EDU
VICE CHAIRMAN:
Fred Sperry (ECB-TOC)
W - 608-264-9698
H - 608-833-6074
FRED.SPERRY@MAIL.ADMIN.WISC.EDU
SECRETARY:
Neal McLain (CTI)
W - 608-831-4636
NMCLAIN@MACC.WISC.EDU
TREASURER:
Stan Scharch (WISC TV)
W - 271-4321
H - 831-1168
CHAPTER 24 COMMITTEE APPOINTEES:
Membership - Leonard Charles
Sustaining Membership - Fred Sperry
Strategic Plan - Denny Behr
Newsletter - Mark Croom
Program Committee:
Mark Croom 271-1025
mcroom@aol.com
Denise Maney 277-8001
Kerry Maki 833-0047
Steve Zimmerman 274-1234
Special Events - Kevin Ruppert
Certification and Education:
Jim Hermanson 836-8340
Tim Trendt (UW-Platteville)
Frequency Coordination: Tom Smith
608-263-2174 (work)
SMITHT@VILAS.UWEX.EDU
SBE National Board Member & Chapter Liaison:
Leonard Charles
W - 271-4321
FAX - 271-1709
LCHARLES@WISCTV.COM
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AMATEUR RADIO NEWS
by Tom Weeden, WJ9H
A proposal to delete the Morse Code requirement in the
international radio regulations was submitted by the New Zealand
delegation to the 1995 World Radio Communication Conference (WRC-
95) in Geneva on October 31. The current requirement of the
International Telecommunications Union (ITU) is that amateur
radio operators worldwide demonstrate Morse Code proficiency in
order to be licensed to operate below 30 MHz. While some other
administrations expressed support of the New Zealand proposal,
most parties opposed the change or said the time was not right
for change. The proposal may be added to the agenda of a future
WRC in 1997 or 1999.
At a time when many believe that the usefulness of Morse code is
nearing its end due to the proliferation of digital technology,
Dr. Tom King, WF9I, of the University of Wisconsin-Eau Claire,
has been adapting Morse code to make it possible for people with
communicative disorders to talk with others. Dr. King, writing
in "MORSEls," says that this 160-year-old encoding system
developed by Samuel F.B. Morse is now being harnessed for those
with limited movement or sensory capabilities as an alternative
computer access method. About 20 manufacturers/developers of
Morse-input hardware or software have been identified to date.
"Morse 2000" is a new outreach program promoted by Dr. King which
will promote the use of, research in, and standardization of
Morse code in rehabilitation contexts, as well as in other
specialized communications settings.
Regional repeater frequency coordinators met in St. Charles, MO,
on October 7 to deal with coordination issues and to hear the
FCC's position on those issues. One coordination problem is that
different regions have different and sometimes conflicting
frequency coordination policies. Deputy chief of the FCC's
Wireless Telecommunications Bureau, Ralph Haller addressed the
group, saying, "I've never been comfortable with the notion that
there was no official recognition of a coordinator in a given
area." The coordinators voted overwhelmingly that it wanted a
"Point of Contact" between the frequency coordinating community
and the FCC. The group further decided (by a narrower margin)
that it wanted the American Radio Relay League (ARRL) to provide
this contact. The group elected a five-member committee to
develop a proposed Memorandum of Understanding to define the role
of the "Point of Contact."
(Excerpts from December 1995 "BADGER STATE SMOKE SIGNALS" and
December 1995
"QST" Magazine)
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NOTES FROM THE CHAIR
by Paul Stoffel
EAS TELECONFERENCE
The EAS satellite teleconference, produced by SBE Chapter 24,
originated from the site of the 1995 Broadcasters Clinic in
Madison, Wisconsin on November 15. Speakers SBE EAS Committee
Chair Leonard Charles and Wisconsin State Emergency
Communications Committee Chair Gary Timm talked about the FCC's
Emergency Alert System without the assistance of furloughed
Federal employee Frank Lucia, author of the EAS. Timm gave
presentations about the EAS at the National and State levels,
while Charles detailed the EAS at a Local level. At the end of
the 90-minute teleconference, a question and answer period
included telephone calls from SBE chapters across the country.
Planning for the EAS teleconference began in the Spring of 1995.
Once donated satellite time was secured from PBS Broadcast
Operations, teleconference planning chugged full-steam ahead.
The months leading up to November included many meetings to
discuss the teleconference's content, graphics, lighting,
electrical power, site preparations, telephones, publicity, and
the pending (and eventual) federal government shutdown.
There are many people to thank who made this teleconference
possible:
Leonard "Chuck" Charles, producer and presenter
Gary Timm, presenter
Paul Stoffel, production coordinator
Chuck Roth, director and MAC graphics
Chris Barker, lighting and production supervisor
Tom Brownrigg, engineering supervisor
Bob Goessling, technical director
Tom Weeden, Chyron graphics
Mike Norton, still store
Stan Scharch, telephones and uplink truck
Don Sanford, lighting
Vicki Way, camera
Marjorie Lueder, camera
Shawn Jones, camera
Chad Theilen, camera
Jamie McCloskey
Fred Sperry, phone operator
Paul Kelly, audio
Joe Tannerbauer, video
Jim Stellpflug, videotape
Justine Driessens, floor manager
Tom Smith, videotape editor and house PA
Kevin Ruppert, SBE booth
Don Borchert and John Laabs, Broadcasters Clinic 1995
LOCAL EAS PLANNING COMMITTEE
Help is needed from Chapter 24 members to begin planning and
implementing the Emergency Alert System for our area. The
committee would include representatives from our chapter, Dane
County Emergency Government, amateur radio, National Weather
Service, State Emergency government, local broadcasters and law
enforcement. Please contact Paul Stoffel at
stoffel@vilas.uwex.edu or 263-2175.
CHAPTER 24 BBS RETIRES
For over five years, the Chapter 24 BBS has been a common
communications path for members. Three years ago, Chris Cain,
WISC-TV, took over sysop duties of the Chapter 24 BBS from
originator Dave Willow. Recently, with the growth of e-mail and
Internet accessibility, the BBS has been used very little by
Chapter 24 members. Therefore, it has been decided to retire the
BBS as of January 2, 1996. Many thanks to Chris Cain for
providing the service. Looking to the future, Chris has
volunteered to design a Chapter 24 homepage available through the
World Wide Web on the Internet. Thanks to Electrotex, Houston,
Texas, for providing Internet services to the SBE. Other
chapters' homepages can be found by connecting to the National
SBE homepage at www.sbe.org(.) Chris said Chapter 24's homepage
will be up soon.
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LOCAL LEGALS
By Tom Smith
PROPOSED
The following parties have applied for permission to construct a
new FM station in De Forest, Wisconsin, on 93.1 MHz.
Louis George Fortis (404 S. Blount ST. # 203, Madison, WI 53703)
with transmitter to be located at Meixner Road, .7 km North of
Hwy V, 5 km NE of De Forest. Antenna will be at 100 m with ERP
of 6 kw.
Walter A. Wigglesworth (RTE. 1, 7171 Hwy 113, Dane, WI 53529)
with transmitter located .98 km N of WIBU and Richards Roads.
Antenna will be at 100 m with ERP of 6 kw.
Jolene Neis (908 W Mohawk Trail, De Forest, WI 54532) with
transmitter located at 4025 Hwy V and antenna at 100 m with ERP
of 6 kw.
David and Lynn Magnum (105 E Veterans St., Tomah, WI 54660) with
antenna at 100 m and ERP of 6 kw. The Magnums own WTMB (AM),
WBOG (FM), WUSK (FM), all in Tomah, and WUSX (FM) in Portage, WI.
(Compiled from BROADCASTING and CABLE)
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NOVEMBER MEETING MINUTES
by Neal McLain
Chapter 24 of the Society of Broadcast Engineers met on
Wednesday, November 15, 1995, at the Ramada Capital Conference
Center, in Madison. This meeting was held in conjunction with
the 1995 Broadcasters' Clinic.
There ware many guests present, several of whom were members of
other SBE chapters. Attendance:
SBE Members: 44
SBE Certified: 31
Guests: 20
Total: 64
The meeting was chaired by Chapter 24 Chairman Paul Stoffel.
Call to order: 7:32 pm.
The chair recognized the Chairmen of other SBE chapters present
at the meeting.
The chair presented national awards which had been received by
the chapter or its members during at the Annual Awards Banquet
held in New Orleans on September 9, 1995:
Best SBE Chapter Newsletter: Chapter 24, Madison, Wisconsin;
editors, Paul Stoffel and Mark Croom.
Best SBE Chapter Frequency Coordination Effort: Chapter 24,
Madison, Wisconsin; Frequency Coordinator: Tom Smith.
Best Technical Article or Program by a SBE Member: "Fiber
Optic OSP," Neal McLain, author.
Best Article, Paper or Program by a Student Member: "Madison
Marathon," James Stellpflug, author.
Adjournment: 7:40 pm.
The business meeting was followed by the National EAS
Teleconference.
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GEOSTATIONARY ORBITS (Part 5: Inclined Orbits)
Neal McLain
(Electronic Editor's note: There are many illustrations in
Neal's article that were not able to be reproduced in this text
version. Please contact Neal for a hard copy of his article
complete with the illustrations)
This is the fifth, and last, in a series of articles about
geostationary orbits; i.e., the orbits occupied by communications
satellites which remain at fixed points in the sky. This fifth
article describes inclined-orbit satellites.
SATELLITE DRIFT
A satellite intended for radio communications among fixed earth
stations must meet two criteria:
The satellite must remain at a fixed position in the sky. As we
have noted in previous articles in this series, this means that
the satellite must move in a geostationary orbit. The owners of
most geostationary satellites try to maintain their satellites
within a box measuring 0.1=F8 x 0.1=F8.
The satellite must be maintained at the proper attitude. This
term describes the orientation of the satellite within its box.
If the satellite is not maintained at the proper attitude, its
antennas will not be aimed properly.
Unfortunately, once a satellite is placed in proper position and
attitude, it doesn't stay there: it tends to drift. Drift
degrades satellite performance in two ways: the satellite may
move out of position, or it may assume an improper attitude.
Drift results from external forces. While there are hundreds of
external forces acting on the satellite, the primary forces are
these:
The gravitational pull of the sun. The intensity and direction
of this force changes continuously, in daily, yearly, and 55-year
cycles. The cyclic nature of this force tends to cause it to
cancel itself: an easterly pull at one part of the cycle is
offset by a westerly pull half a day later; similarly, a
northerly pull is offset by a southerly pull. Nevertheless,
there is a net resultant force which, over the course of several
months, causes the satellite to drift away from its geostationary
position.
The gravitational pull of other objects in the solar system.
Although these forces are considerably weaker than the sun's
gravity, their effects can be measured and predicted. Precise
orbit calculations usually account for the moon's gravity, and
frequently include the gravitational forces of other planets as
well.
The uneven distribution of land mass on the surface of the earth.
Figure 1 illustrates this situation: note that the vector to the
earth's apparent center of gravity (Point G) is not congruent
with the vector to the earth's geometric center (Point C). In
the case of geostationary satellites visible from North America,
the land mass of South America tends to cause them to drift to
the east.
ROCKETS
To counteract these forces, the satellite must be fitted with
some mechanism to move the satellite back into position when it
drifts. In outer space, only one such mechanism is available:
the rocket.
Now, let's stop and discuss rockets. The popular conception of a
rocket is something very large which burns some sort of fuel to
produce an enormous thrust.
More generally, a rocket is any device which produces a force by
ejecting mass. Fuel-burning rockets produce force by ejecting
the products of combustion. But combustion isn't necessary: any
mechanism for ejecting mass will produce a force. A common
example: a loose balloon flying around the room ejecting its air
supply.
The direction of the force produced by a rocket is equal and
opposite to the force required to eject the mass. This, of
course, is Newton's Third Law: for every force, there is an equal
and opposite reaction force.
STATIONKEEPING
Communications satellites are fitted with small rockets called
THRUSTERS. On command from a control station, a thruster is
"fired"; during the "firing", it ejects a gas called fuel or
propellant. Like the air escaping from the balloon, the ejected
gas produces the force. In spite of the terminology, there is no
actual combustion; the terms "fire" and "fuel" are misnomers
carried over from combustion rocketry.
A ground control station precisely controls all parameters
involved in a firing: the position of each thruster relative to
the satellite, the timing and duration of each fire, and the
pressure of the ejected propellant. If these parameters are
controlled properly, the satellite can be maintained at proper
position and attitude for years.
This process is called STATIONKEEPING.
SATELLITE LIFE EXPECTANCY
Every time a thruster is fired, propellant is used. Once the
supply of propellant is exhausted, the satellite cannot be
maintained at proper position and attitude, and the satellite
must be retired. Propellant capacity is the primary factor which
determines the useful life of a communications satellite.
It is easy to understand that a primary goal of every satellite
owner is the conservation of propellant. Many computer studies
have been done to determine the optimum trade-off between
satellite stability and propellant usage.
These studies have shown that a substantial majority of the
propellant is used for just one stationkeeping function: keeping
the satellite from drifting along its north-south axis. Kent
Carson, director of advanced programs for Comsat Systems
Division, has stated that between 80% and 90% of the propellant
is used for this function alone (1).
INCLINED ORBITS
Let us consider what happens if the owner of a satellite simply
stops north-south stationkeeping, and lets the satellite drift
freely along its north-south axis.
Two things happen:
1. The orbit plane becomes INCLINED with respect to the earth's
equatorial plane.
Figure 2 illustrates this situation. In Figure 2(a), the
satellite is at its maximum northerly excursion. In Figure 2(b),
half a sidereal day later, the satellite has moved to the other
side of the earth. However, because the orbit plane passes
through the earth's center of gravity (Kepler's First Law), the
satellite is now at its maximum southerly excursion.
>From a point on the earth's surface, the satellite appears to
oscillate along its north-south axis at a rate of one cycle per
sidereal day.
2. For reasons beyond the scope of this article (conservation of
angular momentum), the orbit assumes a slightly elliptical shape.
As a result, the satellite no longer moves at constant velocity
(Kepler's Second Law). From a point on the earth's surface, it
appears to oscillate along its east-west axis at a rate of two
cycles per sidereal day.
If we combine these two apparent motions, the result is an
elongated "figure-8" pattern. The satellite completes one
complete cycle around the figure-8 pattern each sidereal day.
As the satellite continues to drift, the figure-8 pattern becomes
larger and larger.
Figure 3 illustrates this pattern for GStar 3, as it appeared
from Madison during November, 1995.
ECONOMICS
>From the point of view of a satellite owner, the economics of
this situation are compelling. On one hand, the revenue derived
from leasing transponder time on an inclined-orbit satellite is
considerably less than the revenue which could be realized from a
truly geostationary satellite. On the other hand, propellant
usage is cut dramatically, thereby extending the useful life of
the satellite, often by several years. The potential revenue to
be derived from this extended life more than offsets the revenue
lost through reduced transponder pricing.
It comes as no surprise, then, that many satellite owners have
allowed their geostationary satellites to drift into inclined
orbits.
BUT IS IT GEOSTATIONARY?
Is an inclined-orbit satellite still "geostationary"?
Strictly speaking, no. In a previous article in this series
(NEWSLETTER, September, 1995), we defined geostationary as
follows:
The orbit must be geosynchronous.
The orbit must be a circle.
The orbit must lie in the earth's equatorial plane.
An inclined orbit is indeed geosynchronous, but it is not a
circle and it does not lie in the earth's equatorial plane.
The FCC's definition is less restrictive:
Geostationary Satellite. A geosynchronous satellite whose
circular and direct orbit lies in the plane of the earth's
equator and which thus remains fixed relative to the earth; by
extension, a satellite which remains approximately fixed relative
to the earth (2).
An inclined-orbit satellite meets the "by extension" part of this
definition as long as it is maintained in the correct east-west
position (to avoid interference to adjacent satellites) and at
the proper attitude (to keep the antennas aimed correctly).
TRACKING
An inclined-orbit satellite poses a problem for the end user: the
earth station antenna must track the satellite. For this
purpose, the antenna must be equipped with a dual-axis steerable
mount and a tracking controller.
A dual-axis steerable mount is a motorized mount which can be
moved independently about two axes. Either of the two types of
mount we discussed last month can be used:
EL/AZ mount. This mount is dual-axis by definition: it adjusts
the antenna in the azimuth and elevation axes.
Polar mount. To be dual-axis, a polar mount must be equipped to
allow adjustment about the declination axis throughout the full
range of the satellite's figure-8 pattern. Figure 4 illustrates
Comtech's dual-axis polar-mounted antenna.
For that matter, the mount doesn't have to be one of the standard
mounts we discussed last month. Andrew makes an interesting
hybrid mount (Figure 5): the up-down axis is elevation; the east-
west axis is neither hour angle nor azimuth, but falls somewhere
in between.
The tracking controller moves the antenna automatically to track
the satellite. Two types of controller are available
commercially:
AGC-controlled. This type of controller monitors the level of
the received signal (typically by monitoring receiver AGC
voltage), and moves the antenna periodically to peak the signal.
Most AGC-controlled controllers are equipped to maintain a
history of the figure-8 pattern. The history is established
during the first day's operation; thereafter, the history is used
in two ways: it tells the controller which way to move the
antenna when peaking the signal, and it allows the controller to
continue tracking if the satellite signal fails.
The controller updates the history during the course of normal
tracking. Thus, it responds automatically to changes in the
shape of the figure-8 pattern as the satellite continues to drift
along its north-south axis.
AGC-controlled controllers move the antenna in a series of short
steps. For this reason, they are sometimes called step-track
controllers. The original data used to generate Figure 3 was
produced by an AGC-controlled controller; note that the
individual steps are clearly evident in this illustration.
Ephemeris-controlled. This type of controller mathematically
calculates the pointing angles to the satellite and moves the
antenna accordingly. Calculations are based on ephemeris data
programmed into the controller at installation.
This type of controller is capable of moving the antenna
continuously, rather than in a series of steps. This technique
is advantageous in low-signal situations where any change in AGC
voltage would result in degraded signal quality.
Because this type of controller calculates pointing angles from
ephemeris data, it does not respond automatically to changes in
the figure-8 pattern as the satellite drifts. For this reason,
the ephemeris data must be updated periodically. Some satellite
owners periodically download ephemeris data to all receiving
stations.
The functions of a tracking controller can be integrated into a
general-purpose antenna controller. This type of controller can
move the antenna to any satellite, geostationary or inclined.
When moved to an inclined-orbit satellite, the satellite is
located by reference to the history or ephemeris data.
References:
(1) Scott Chase. "Earth Station Technology: Keeping Up with
Orbital Capabilities." Via Satellite, May, 1991, Page 24.
(2) Code of Federal Regulations, Title 47, Section 2.1.
Washington: United States Government Printing Office, 1992.
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BROADCASTER'S CLINIC PROVIDES INFORMATION FOR EVERY ENGINEER
By Steve Paugh, MEG Communications
The 41st Broadcast clinic was very symbolic of the change that is
invading our industry. We met in familiar soundings but the
Clinic site has a new name. What was the Holiday Inn South East
has been purchased by one of Wisconsin's Indian Tribes, renamed
the Ramada Inn and by the time we return next year, will be part
of a bingo and gaming complex. If that is not representative of
the change that runs rampant in our industry, nothing is.
Terry Baun's opening remarks set the stage for our three days of
seminars. Since the FCC no longer requires licensed engineers in
the broadcast plant, there are fewer engineers employed in
broadcasting. Terry went on to remark that by the turn of the
century, 50% of the people currently in broadcast engineering
would no longer be in a full time engineering position. Many
will become contract engineers or will perform engineering duties
for more than one facility. It is up to us to decide what
portion of the 50% we want to become. To prepare for the future,
engineers have to become business people, to turn their
departments into profit centers, not burdens on the bottom line.
It is through seminars like the Broadcast Clinic that we can
embrace these changes and use them to our advantage.
David Gerstmann of WireReady carried this theme forward by
describing how he found a low cost solution to a problem his
station was having with increasing costs of wire service
maintenance. David feels that there are many problems that can
be solved with the application of inexpensive personal computers,
off the shelf hardware and our own ingenuity with software.
As an example of what others have done in new facilities
construction, we had two video tours of new facilities. The
first was WTMJ's new AM facility in Milwaukee which was an
example of a first class facility designed to awe future
generations of engineers. The incredible attention to detail in
this facility is the result of a dedicated and supportive
ownership that is rarely seen in these days of ever shrinking
budgets. We also were treated to an evening session were Chris
Cain of WISC-TV showed us a video log of the construction of the
new Madison Community Candelabra Tower project. This tower is
the principal transmission site for 3 television stations,
several FM's, and numerous governmental, private and commercial
communications services. Chris's video tour concluded with a
very realistic ride to the top of the tower in the service
elevator. The camera had a mic on it, and I never realized how
many scary creaks and groans a tall tower makes when you are
riding up the interior. These two projects span the full range
of new construction. The AM project was a one owner project with
an opportunity to build the best. The Candelabra project
represents the joining together of numerous parties who have
competing interests but who have banded together to do something
that no one owner alone could afford to do. I believe that in
the future we will see more of the latter and fewer of the
former. This is all part of the changes that will be affecting
all of us.
Computers are the new broadcast tool and we had six sessions
covering the merging of computer and broadcast technologies. We
had a tour of the Internet and immediately discovered that the
"Internet sky's" are crowded even at 10PM. We were also
impressed how quickly one can "fly" from computer to computer,
even when the other computer is half-way around the world. The
use of LANs (Local Area Networks) in broadcast and production is
moving rapidly from the front office to the back room. If you
resisted LANs up to now because they're just "office equipment"
you had better re-think your position. LANs carrying audio are
making their way into many facilities, LANs carrying video are
not far behind. Topics presented covered the various types of
LAN cabling, connectors and disk based storage systems. ISDN is
moving from the realm of the unique to the common place.
Tektronix showed their latest version of their disk recorder that
looks like a very promising product. BTS had their disk based
file server on display. If D2 was touted as a "drop-in"
replacement for an analog VTR, the digital disk recorder is on
the verge of becoming a drop-in replacement for the tape based
VTR.
We had updates on two topics covered last year. The AM radio
NRSC compliance update session by Greg Buchwald stressed the
importance of limiting the AM passband to 10khz to prevent
interference to adjacent channel stations and the resulting
"knock on the door". Now that the broadcasters have done their
part, we as consumers are still waiting for manufactures to widen
receiver passbands from the current 5khz to 10KHz. Tom Keller
reviewed the results of the Digital Audio Radio field tests
conducted in Cleveland, Ohio. The 1200 page report basically
says that there are some problems to be solved before DAR can be
fully implemented.
The Wednesday evening SBE meeting was capped with an SBE National
Teleconference on the new Emergency Alert System (EAS) which is
replacing the Emergency Broadcast System (EBS) which was derived
from the old Conelrad system (remember those upside down
triangles on your AM radio dial?). The EAS replaces the annoying
alert tone with a much more annoying burst of data. Under the
old system a voice would announce "this is a test of....",
followed by the tone. Now all the FCC will require is the
transmission of the raspy data burst with no voice explanation.
The advantage of the new system is that the data burst carries
all of the particulars of the warning. This allows any computer
to decode the warning and convert it to text. The disadvantage
is that the data is sent in the clear with a minimum of 80%
modulation and is quite audible to the listener. The consensus
of the teleconference attendees was that the system would be
implemented as is but there may be a reconsideration by the FCC
after input from the broadcasters and the public.
One of the really interesting sessions was a product that was the
result of military R&D that had a broadcast application. A
system built by Litton was designed to extract very pure Nitrogen
from the outside air to provide an inert atmosphere inside
helicopter fuel tanks as the fuel is used up. This prevents an
explosive atmosphere from forming in empty fuel tanks. Litton
made the observation that broadcasters use Nitrogen for keeping
transmission lines free of moisture. They came up with a system
to eliminate the need for Nitrogen tanks by adapting their
helicopter system to broadcast use, a truly great idea.
Two other new technology items were a single tube 60KW UHF TV
transmitter by Acrodyne that uses an active device they call a
Diacrode. This "tube" is the diameter of a basketball, but only
half as high, weighing about 20 pounds. Incredible. Comark
Communications described their new transmitter power supply that
is basically a very high power switch mode power supply having
improved short circuit overload characteristics.
Panasonic laid out their new digital video cassette system called
DVCPRO, a "professional" version of the Digital Video Cassette
originally developed as a digital replacement for consumer VHS
that would be compatible with the future HDTV system. The
professional version of DVC records at twice the data rate of the
consumer DVC version. DVCPRO has playback compatibility with DVC
tapes. A DVCPRO studio deck will sell for half the cost of a
Beta-SP deck while giving comparable quality. The interesting
part is that a DVC field camera will go for about $4000, and will
record 1 hour on a cassette the size of an audio micro-cassette.
Sony countered with their system that will be called Betacam SX,
an apparently digital system using UVW tape. Details are still
very sketching at this point, more at NAB. Sony is promoting
their vision of the future using video servers and video
networks. All of the new systems share the commonality of
component digital video. The variables are in the sampling and
compression methods.
Fifty vendors exhibited their products at the show, making this
one of the most successful shows in a long time. Manufactures
are introducing more computer based solutions, but the high
startup costs of these new products are keeping price points near
traditional based solutions. As sales increase, we can expect
the computer based products to offer more features and lower
cost.
In summary, the 41st Broadcast Clinic was an excellent program
covering all aspects of engineering. By looking at various
disciplines we get to "take the blinders" off and get a greater
sense of how we individually fit in to the big picture. The
Clinic is an opportunity to recharge our professional batteries,
and is an excellent warm-up for the NAB. See you next year!
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THANKS TO ALL OUR
SUSTAINING MEMBERS:
BTS
Broadcast Communications
CTI
Clark Wire and Cable
Comark Communications
Electronic Industries
Emmons Associates
Fuji Film I&I
Maney Logic
MRC Telecommunications
Panasonic Broadcast
Roscor Wisconsin
Scharch Electronics
Skyline Communications
Sony Broadcast
Tectan, Inc.
Teleport Minnesota
3M Audio & Video
Video Images
WISC-TV 3
WKOW-TV 27
WMSN-TV 47
WMTV-TV 15
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NATIONAL SBE PHONE DIRECTORY
SBE National Office
8445 Keystone Crossing Suite 140
Indianapolis, IN 46240
Main Number 317-253-1640
Engineering Conference Line 317-253-0122
Job Line 317-253-0474
Fax 317-253-0418
BBS 317-253-7555
President: Chuck Kelly CBT
Broadcast Electronics
P.O. Box 3606
Quincy, IL 62305
W 217-224-9600
F 217-224-9607
H 217-228-7373
CIS ID# 70307,2642
InterNet: kelly1@ixc.net
Vice President: Terrence Baun CPBE
Criterion Broadcast Services
5300 W. Garfield Avenue
Milwaukee, WI 53208
W 414-449-5300
F 414-449-5380
CIS ID# 71525,1060
Secretary: Keith Kintner CSTE
KLCS TV 58
1061 W. Temple Street
Los Angeles, CA 90012
213-625-6958
F 818-362-5294
CIS ID# 72530,620
InterNet: keith.kintner@gur.com
Treasurer: Bob Goza CPBE
KMOV TV
3315 Highway 50
Beaufort, MO 63013
314-484-3718
F 314-484-3840
InterNet: rgoza695696aol.com
Executive Director: John Poray CAE
SBE National Office
8445 Keystone Crossing Suite 140
Indianapolis, IN 46240
W 317-253-1640
F 317-253-0418
BOARD OF DIRECTORS
Jim Bernier CBT
WTVH, Inc.
980 James Street
Syracuse, NY 13203
315-425-5503
F 315-425-5513
InterNet: 72037.1723@compuserve.com
David Carr CPBE
KHOU-TV
P.O. Box 11
Houston, TX 77001
713-284-8741
F 713-284-8700
Leonard Charles CSTE
WISC TV
7025 Raymond Road
Madison, WI 53719
608-271-4321
F 608-271-1709
InterNet: lcharles@wisctv.com
Dane Ericksen PE CSRE CSTE
Hammett & Edison, Inc.
Box 280068
San Francisco, CA 94128-0068
707-996-5200
F 707-996-5280
Michael Fast CPBE
WCBM Radio
1303 Burleigh Road
Lutherville, MD 21093
410-356-3003
F 410-581-0150
Michael McCarthy CBRE
WLIT FM/Viacom International
150 N. Michigan Ave., #1135
Chicago, IL 60601
312-329-9002
F 708-439-1464
P 800-592-3058
Edward Miller CPBE
WEWS Scripps Howard
3001 Euclid Ave
Cleveland, OH 44115
216-431-3687
F 216-431-3641
Troy Pennington CSRE
WZZK AM/FM, WODL FM Radio
530 Beacon Parkway W. #300
Birmingham, AL 35209
205-916-1119
F 205-916-1151
Robert Reymont CPBE
Nationwide Communications, Inc.
P.O. Box 5159
Mesa, AZ 85211-0500
602-964-4000
F 602-644-7660
CIS ID# 71645,254
Internet: NCIRADIO@CRL.COM
Martin "Sandy" Sandberg CPBE
Consultant
9807 Edgecove Drive
Dallas, TX 75238
214-343-5786
F 2114-343-9807
John Schneider CBRE
RF Specialties of Washington, Inc.
19237 Aurora Avenue N.
Seattle, WA 98133
206-546-6546
F 206-546-2633
CIS ID# 74603,3342
Tom Weber CSTE
WISH TV 8
1950 N Meridian St.
Indianapolis, IN 46202
317-921-8535
F 317-926-1144
CIS ID#: 73250,215
Chris Imlay, Esq.
SBE General Counsel
Booth, Freret & Imlay
1233 20th St. NW Suite 204
Washington, DC 20036
202-296-9100
F 202-293-1319
James Wulliman, CPBE
Ennes Director
721 W. Calle Del Regalo
Green Valley, AZ 85614
Phone and Fax 602-648-1250
NATIONAL OFFICE STAFF
Linda Godby, Certification
Peggy Hall, Membership
Sarah Hayden, Signal/Conferences
Julie Dinger, Secretary
317-253-1640
F 317-253-0418
Job Line 317-253-0474
BBS (N,8,1) 317-253-7555
NATIONAL COMMITTEE AND TASK FORCE CHAIRS
Executive Committee........................Andy Butler, Tom Weber
By Laws Committee....................................Rick Edwards
Certification Committee..............................Jim Wulliman
Chapter Awards Committee............................Larry Wilkins
Chapter Liaison Committee..........................John Schneider
EAS Committee.....................................Leonard Charles
Electronic Communication Committee....................Jim Bernier
Engineering Conference Committee...................Jerry Whitaker
FCC Liaison Committee...............................Dane Ericksen
Fellowship Committee....................................Mike Fast
Finance Committee....Bob Goza (Chair), Marvin Born, Keith Kintner
Frequency Coordination Committee....................Mike McCarthy
Futures Committee....Ed Miller (Chair), Andy Butler, Jim Bernier,
Marvin Born, Mike Fast, Tom Weber
Industry Relations Committee..........................Andy Butler
International Committee...............................Chuck Kelly
Membership Committee.................................Dave Johnson
Nomination Committee...............................Robert Reymont
State Broadcast Assn Liaison Committee.............John Schneider
Sustaining Membership Committee.........................Tom Weber
HF Broadcasting Liaison............................Doug Garlinger
SBE/AMITRA Frequency Coordination Liaison..............David Carr
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