Edited by: Mike Norton

Electronic Version: Leonard Charles
Electronically Distributed by Chris Cain
Contributors this month:
Tom Smith
Chris Cain
Tom Weeden
Neal McLain

Articles Welcome!! Send correspondence to:
SBE Chapter 24 Newsletter Editor
46 Trillium Court
Madison, WI 53719-2308
or Email at Mike_Norton@wetn.pbs.org

About this Newsletter
Meeting Announcement
Upcoming Meeting Schedule
June Meeting Minutes
WBA Mock FCC Inspections
HAM Radio Update
Small Businesses Lose In Auction
FCC Rulemakings
CABLE-TEC EXPO '96
Broadband Networks (Pt 4)
A Technical Curiosity: The "True" 3-Way Splitter
Video Chief Engineer Wanted
Sustaining Members Listing

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PLAYGROUND - HORSE SHOE TOURNEMENT - BASEBALL
Horse shoes provided. Bring your own bat, ball and gloves. Also Volleyball and Basketball courts available. Feel Free to bring your own grill, lawn chairs, or blankets. RESTROOMS and WATER available near the shelter. Picnic tables and electrical outlets located in the shelter.

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Treasurer's Report: no report.

Newsletter Editor's Report: no report.

Program Committee (reported by Steve Zimmerman and Denise Maney): The July meeting will be the annual family picnic.

Special Events: no report.

Certification and Education (reported by Jim Hermanson): one person sat for the last examination. The next examination period will be in November; details will be posted on the Chapter's WWW site.

Frequency Coordination Report (reported by Tom Smith): Not much activity; just wireless microphones.

National Liaison Report (reported by Fred Sperry with additional contributions by Kevin Ruppert):
(1) SBE is now offering professional liability insurance.
(2) Membership renewal deadline is June 30.
(3) This year's rebate check has been received from the national headquarters office.
(4) The national headquarters office has suggested that chapters return their rebate checks to headquarters as contributions to the Ennes fund; the Chapter 24 members present did not choose to take this action.
(5) The ONE NEW MEMBER campaign has ended, with successful results: 260 new members.
(6) The recent EAS Seminar, sponsored by Chapter 24, was a "very productive day."
(7) The Wisconsin Broadcasters Association convention in July will include a session about EAS; Leonard Charles and Gary Timm will be featured speakers.

Old business: none.

New business: Kerry Maki led a lively impromptu discussion about the merits of various EAS decoders.

Professional Announcements:
(1) Steve Zimmerman introduced Jerry Van Vliet, now sales representative for Fuji.
(2) Tom Smith discussed pending changes in the FCC's EEO rules.
(3) Steve Paugh requested information about Betacam training.

The business meeting was adjourned at 7:27 pm. The program featured a presentation by Tom Sibenaller, representing Roscor Wisconsin, about the Panasonic DVCPRO equipment.

Submitted by Neal McLain, Secretary

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I would like to conclude this report by listing the remaining "problem areas" that my inspections revealed:

1). EBS Tests: Each licensee must be logging the weekly transmission and receipt of tests whether you are a participating station or not. If equipment is not functioning, appropriate documentation should be made and kept as part of the stations logs for 24 months.

2). Tower Lighting & Marking: The licensee's tower must be marked and lighted in compliance with the Terms of Station Authorization (TSA). Failure of the Lighting system must be noted on the station log and appropriate notifications to the FAA must be made and noted.

3). AM Directional Stations: All licensed parameters such as ratios, phase & monitor point limits must be maintained per the TSA. (Including daytime or night time modes if required.)

4). Public File: Many of the categories in this file must be kept for a specific period of years.

5). Duty Operators: The requirement for these personnel to be licensed has been dropped. However the Duty Operator is still required to know the following:

a). EBS/ EAS: How to run a test.
How to log a received test.
The correct station to monitor.
Where is the EBS Checklist.
b). Licensed parameters per the TSA.
c). Tower Lighting responsibilities per the TSA.

6). Logs: The Station Log for the past 24 months must be available upon inspection.

In these past two articles I have attempted to outline the most important issues that I came across in the series of inspections that I performed.

I recently was informed that the WBA plans on continuing and offering this Inspection Program to all stations in Wisconsin. More specific details will be announced soon by the WBA. This is a very innovative program that goes a "long way" in insuring that the stations in Wisconsin, that participate, are in compliance with current FCC rules.

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The FCC has approved temporary use of rare "1x1" call signs for teams participating in the World Radiosport Team Championship (WRTC) July 13 and 14. The 52 special calls are W6A through W6Z and K6A through K6Z, one for each team competing. WRTC participants come from 30 different countries and were chosen by national Amateur Radio organizations, contest clubs, and an international panel of judges. Teams will operate from similar sites in the San Francisco Bay area running 100 watts, attempting to contact as many amateur stations as possible. This is the second WRTC event held and is sponsored by the International Amateur Radio Union. Awards will also be given to amateurs who are able to contact several WRTC teams.

A new unlicensed radio service located on 14 channels between 462 and 468 MHz has been approved by the FCC. Part 95 of the FCC Rules was amended to create the Family Radio Service, in response to a petition filed by the Radio Shack Division of Tandy Corporation to provide "the American public an affordable and convenient means of direct short-range two-way voice communication among small groups of persons." Range of radios operating in the new service is intended to be a few hundred yards to about a half mile.

(Excerpts from July 1996 "QST" Magazine)
Tom Weeden, WJ9H, is South-Central Wisconsin's SKYWARN Net Manager

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The FCC held it's auction for Personal Communications Service (PCS) Group "C" which was reserved for small business. Instead, the bids came in higher than those for either of the previous two auctions for groups A or B. In many of the markets, the bids were for 2 or more times what large companies such as AT&T and Sprint paid in the same markets. In some markets the bids were 5 times greater.

The bids were so high because the FCC allowed these small businesses to seek up to 75% equity from larger corporations and that they will be allowed to pay the FCC over a 10 year period. Group A and B bidders had to make full payment within a short period of winning their bid.

The winners include Nextwave which won 56 markets including New York and Los Angeles for a bid of $4.2 billion. One of their backers was SONY and a number of Korean corporations. The second largest winner was DCR PCS who bid $1.4 billion for 43 markets including Chicago and Dallas. One of their backers is Westinghouse along with an Asian investment group. The third largest winner was GWI PCS with a bid for $1.1 billion for 14 markets including San Francisco, Miami and Atlanta. One of their backers was Hyundai.

The fourth largest bidders has already defaulted and the FCC was to begin re-auctioning the licenses on July 3rd. That bidder was a corporation named BDPCS which bid $874 million for 17 markets including Seattle and Phoenix. Their backers included Samsung and the regional telephone company US West.

Many small and minority business groups are upset with the auction and at least one plans to sue the FCC. Many small businesses did not bid because of the odds against winning. Many are also questioning if foreign ownership laws are being violated. Chairman of the FCC Reed Hundt called it successful even if many of the 100 bidders received a license to operate in one of the smallest markets.

(From the NY TIMES and BROADCASTING & CABLE)

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The FCC has issued new rules concerning the expiration of licenses of stations which have gone silent. These new rules were mandated by the Telecommunications Act of 1996 and are more strict then in the past.

The new rules require that the license of any station that has been silent for the period of 12 consecutive months shall have it's license revoked, notwithstanding any provision, term, or condition of the license to the contrary. This provision also pertains to stations operating under Special temporary authorizations or under a construction permit.

Low power TV, TV translator, TV booster, FM translator, and FM boosters that fail to operate for a period of 30 days may have their licenses revoked at the discretion of the FCC. Revocation is automatic after 12 months.

Stations that were silent on February 8, 1996, when the Telecommunications law went into effect, have till February 8, 1997 to return to the air or their licenses will be revoked.

This rule was adopted on May 14, 1996 and released on May 17, 1996. It became effective when published in the FEDERAL REGISTER on June 6, 1996, pages 28766-28768.

The FCC has revised the rules concerning both Common Carrier and Private Operational Fixed Service microwave operations. These rules are meant to simplify the rules concerning the various microwave services.

Anyone considering operation of microwaves covered under these parts of the rules should check on all of the changes. This rulemaking was very extensive and took 59 pages in the FEDERAL REGISTER.

These rules become effective on August 1, 1996 and were adopted on February 8, 1996 and released on February 29, 1996. These rules were published in the FEDERAL REGISTER on May 28, 1996 on pages 26670-26728.

The FCC has established a new unlicensed two-way radio service that will allow communication over short distances. This service is meant for use by private parties such as families, friends or other private parties. Suggest uses by the FCC include hunters, hikers, bicyclists and other outdoor activities where there is a need to communicate over short distances. This service differs from CB services as business activities are not allowed on this service.

These radios will operate with a output of a half watt with 14 channels in a frequency range from 462.5625 to 462.7125 and 467.5625 to 467.7125 megahertz. Modulation of the carrier will be FM with a deviation of plus or minus 2.5 kilohertz.

The FCC adopted these rules on May 14, 1996 and released them on May 15, 1996. The rules become effective on July 8, 1996 and were published in the FEDERAL REGISTER on June 6, 1996 on pages 28768-28770.

The FCC has issued a fifth notice of proposed rulemaking concerning the issuing of the technical rules for the adoption of the digital television broadcast standard as proposed by the Advisory Committee on Advanced Television service and with is based on the Grand Alliance System. The FCC is now calling the standard for digital TV "DTV" instead of "ATV" for Advanced TV. This notice seeks comments on the technical standards for digital television and does not address other issues such as simulcasting, allocations, eligibility or other more political issues.

Issues discussed in this notice include scanning rates, audio and video coding, transport (MPEG-2 standard), transmission (VSB), carrier frequency, and RF interference (emission mask). Closed captioning, low-power TV and licensing of the technology are also addressed as well as the impact on a long list of current technical and operational rules. Comments were due July 11, 1996 with replies due August 12, 1996. This notice was adopted May 9, 1996 and released on May 20, 1996. Published in the FEDERAL REGISTER on May 29, 1996 on pages 26864-26872.

The FCC proposes to consolidate the rules concerning blanking interference by AM, FM and TV stations into one section of the rules. They also propose to amend the signal contour determinations by establishing AM and TV blanking areas. This rulemaking also covers broadcasters responsibility in correcting interference problems and creates a list of protected and nonprotected devices.

The proposed contours for blanketing interference areas are 1 V/m for AM stations and the 115 dbu contour for FM and TV. This is the present contour for FM. The FCC is also proposing that broadcasters be libel for correcting problems for longer than the first year after the receiver program test authority that the present rule requires.

The FCC is proposing that stations respond to complaints within 10 working days and resolve complaints within 30 days from that time.

Devices the FCC wishes to add to the list that broadcasters need to correct problems with include most telephone devices, audio amplifiers recording gear, medical electronics, PCS and specialized mobile radio systems. Antenna preamps and malfunctioning equipment would be exempt.

Comments were due on June 25, 1996 with replies due July 25, 1996. This notice was adopted March 21, 1996 and released April 26, 1996. It was published in the FEDERAL REGISTER on May 28, 1996 on pages 26491-26496

The FCC wishes to modify the rules so that pre-1964 shortstations can make minor transmitter modifications and moves easier. These rules would make allow changes that would not create new interference and follows a new interference analysis based on field strength protection ratios and not on the 1 m/v contour of short-spaced stations.

Second and third adjacent protection between short- spaced stations would be eliminated. The FCC would also eliminate the requirement for agreements between short-space stations when they make changes.

These proposed rules would allow short- space station more opportunity to upgrade.

Comments are due July 22, 1996 and replies due August 5, 1996. This notice was adopted on May 23, 1996 and released on June 14, 1996. Published in the FEDERAL REGISTER on June 27, 1996 on pages 33474-33476.

(Compiled from the FEDERAL REGISTER)

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Cable-Tec Expo '96, the annual convention of the Society of Cable Telecommunications Engineers (SCTE), met in June at the recently-expanded Opryland Hotel in Nashville. A firsthand report:

As in previous years, much attention focused on network construction progress. Several MSOs reported completion of rebuild projects in which older coaxial distribution systems were replaced with new HFC (hybrid-fiber coax) systems capable of carrying digital as well as analog signals.

Meanwhile, equipment vendors were obviously standing ready to exploit the growing market for digital terminal equipment. Four product categories dominated the exhibit floor:

-Digital-video distribution systems, capable of transmitting somewhere between six and ten compressed video signals per 6-MHz cable channel. Most of these systems employ continuous digital paths all the way from the satellite uplink to the subscriber's settop converter.

-So-called "cable modem" systems to provide high-speed data transmission paths for PC owners. At the PC, the modem converts the RF signal to an ethernet signal, and an ethernet card in the PC completes the path. At the headend, a router or a server connects the network to a service provider, typically a third-party Internet Service Provider (although some cable companies have established themselves as ISPs).

-Telephony-over-cable. These systems include a side-of-the-house junction box variously called a Network Interface Unit (NIU) or Network Interface Device (NID). Each NIU/NID is equipped with one input port and at least three output ports: an F connector to feed the house coax wiring, and two RJ-11's to feed the house telephone wiring. At the headend, a switch (typically a modified cellular switch) connects the system to the public switched telephone network.

-Network management systems. These systems underscore a fundamental fact about two-way cable systems: two-way is a double-edged sword. On the one hand, two-way systems are a lot more difficult to maintain, but on the other hand, the very fact that they're two-way makes fault-detection and fault-reporting possible. Network management systems employ a variety of fault-detection devices throughout the network, each capable of reporting faults back to a the network-management processor at the headend.

Other items, briefly noted:

-TCI formally announced that their end-to-end digital video system, called HITS (Headend in the Sky), will be launched in October, 1996. However, they weren't able to announce the programming lineup yet due to ongoing negotiations with program suppliers.

-There seemed (to me) to be surprisingly little activity in the EAS arena, even though Frank Lucia (FCC) was a speaker at one of the breakout sessions. Apparently, equipment vendors are still waiting for release the FCC's pending Second Report and Order.

-The FCC has formally adopted a numbering-assignment plan for analog cable channels. Under this plan, cable channel numbers are standardized all the way up to Channel 158, topping out at 1,002 MHz. The proposed plan has been submitted to EIA as draft standard EIA-IS-132; however, the EIA still hasn't adopted it even through the FCC has incorporated it into the rules.

-If exhibit-booth size is any guide, Lucent Technologies (formerly AT&T Network Systems) clearly intends to be a major cable-industry equipment supplier.

This year's SCTE Expo was the first national convention to meet at the Opryland Hotel since the completion of an extensive expansion of the hotel's convention facilities. Several hundred new guest rooms, several large ballrooms, and two large exhibit halls have been added, all done in the same fake-antebellum architectural style of the original Opryland. Gaylord Entertainment, owner of the hotel (as well as The Nashville Network and several other media-related properties) had solicited SCTE as its first customer in recognition of Gaylord's own long-standing association with the cable television industry.

A highlight of the convention was a tour of other Gaylord properties located within the Opryland complex near the hotel, including The Nashville Network's studio facility, the Grand Old Opry House, and the Grand Old Opry Museum. TNN's studio facility looked much like a major-market TV station except that it doesn't have a transmitter. TNN now uplinks four 24-hour video feeds from its studio: The Nashville Network, TNN International, Country Music Television, and Z Music Television.

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Editors note: There are many figures offering pictoral representation of Neal's text. These figures were not reproduced in the Electonic version of the newsletter. Hard copy can be obtained by contacting the editor of the hard copy version of the newsletter.

This is the fourth in a series of articles about coaxial broadband networks. In this article, we'll discuss passive splitting devices: splitters, directional couplers, and taps.

THE BASIC 2-WAY SPLITTER

As we noted in a previous article in this series(1), if a signal must be split, the characteristic impedance of the circuit must remain constant. This is accomplished by a device known as a hybrid splitter, or simply a splitter.

Splitters are characterized by two losses figures: insertion loss and isolation loss.

Insertion loss

Actual production-line splitters introduce higher insertion losses, typically 3.5 to 4 dB. The additional loss results from slight impedance mismatches in the internal circuitry.

A splitter can be connected "backwards," with the signal passing from the output to the input; this configuration is frequently used for combining signals of different frequencies. Insertion loss is the same in either direction: a signal passing from output to input is subject to the same loss as a signal passing from input to output.

Isolation loss

MULTIPLE-OUTPUT SPLITTERS

Two or more 2-way splitters can be installed within a single housing to create multiple-output splitters. Several configurations are available commercially, including 3-way, 4-way, 6-way, 8-way, and 16-way.

A 3-way splitter consists of two 2-way splitters in one housing (Figure 2); it divides the input signal into three outputs. These outputs are not equal; they identified as follows:
"High Leg" (one output) -3.01 dB.
"Low Leg" (two outputs) -6.02 dB.
More elaborate splitters are simply combinations of the same basic 2-way splitter.

A directional coupler is an unbalanced splitter: it splits the input signals into two unequal outputs(3).
The two outputs of a directional coupler are usually designated "output port" and "tap port". Losses are designated as follows:

Input Port to Output Port: insertion loss.
Input Port to Tap Port: tap loss.
Output Port to Tap Port: isolation loss.

The input power is divided between the output port and the tap port; the higher the tap loss, the lower the insertion loss. Directional couplers can be designed to provide just about any tap-to-out ratio desired, although most commercially-available units are manufactured in 3- or 4-dB steps.

Isolation loss is (more or less) independent of the tap-to-out ratio; typical units exhibit about 20 dB. Like splitters, directional couplers are designed for maximum isolation loss.

A tap consists of a directional coupler and one or more splitters in a single housing. Each tap provides one output port and two or more tap ports.

Taps are used in feeder lines to generate subscriber drops. At each tap, drops are connected to the tap ports, and the output port feeds on down the line to the next tap.

The tap is probably the single most common device found in a broadband network. It is the basic device used at the junction between the feeder and the drop portions of the distribution plant. In aerial distribution plant, taps can be easily observed on utility poles, usually attached to the cable-support strand.

Taps are typically available in 2-way, 4-way, and 8-way configurations. Note that:
-Taps are identified by tap loss, and are available in 3-dB steps.
-Most taps provide one output port; however, three special terminating taps provide only tap ports. These taps contain only splitters. A terminating tap can be used only at the end of a feeder line.
-As theory predicts, insertion loss decreases as tap loss increases -- up to a point. However, insertion loss never drops below about 0.5 dB: again, we're limited by impedance mismatch losses in the internal circuitry.

Splitters, directional couplers, and taps are available in two packaging configurations:
-Drop devices are intended to be used in the drop portion of the distribution system. They are generally fairly small (one or two cubic inches), and are equipped with "F" connectors for use with drop cable. Drop devices are usually installed indoors, although they can safely be installed outdoors if the connectors are properly weather-protected.
-Line devices are intended to be used in the trunk and feeder portions of the distribution system. They are generally much larger (3" x 4" x 5" is typical), and are fitted with large (5/8"-diameter) connectors for use with hard cable. Line devices are usually installed outdoors; in aerial plant, they are usually bolted directly to the strand.

Next month we'll discuss typical applications: premises wiring and feeder lines.

(1)"Broadband Networks," Part 2. SBE Chapter 24 Newsletter, May, 1996.
(2)Many older television sets produce spurious signals at their local oscillator frequencies. I've encountered sets which produce so much spurious LO signal at the VHF input terminals that it exceeds the amplitude of the incoming cable signal. On a spectrum analyzer display, the LO spike is sometimes clearly visible, marching up and down the band as a nearby subscriber tunes his television set.
(3)Of course, we could just as well say that all 2-way splitting devices are directional couplers, and that a 2-way splitter is simply a special case in which the two outputs happen to be equal.

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Over the years, various cable-television equipment manufacturers have produced "true" 3-way splitters. A true 3-way divides the input signal into three equal output signals. The theoretical insertion loss can be calculated from our familiar formula:
dBwatts = 10 log (P2/P1) = 10 log (1/3) = -4.77 dB.

These are interesting devices, but they've never been successful commercially. Why? I think there are two reasons.

First of all, they're expensive: one 3-way usually costs more than two 2-ways. Apparently, it's a tricky device to build, requiring manual adjustment to get the three output signals balanced.

But the second, and probably more important, reason is demand: there simply aren't many applications where three equal signals are required. Consider residential installations: how many homes have exactly three TV sets, all located at exactly the same distance from the incoming cable drop?

Today, a true 3-way splitter is about as rare as a two-dollar bill: an odd technical curiosity displayed on an office bookshelf or the dashboard of a truck.

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College of DuPage is seeking a skilled Chief Engineer for our video facility. This is a fast-paced production facility with a crowded schedule of live video satellite uplinks, two busy distance learning networks, multiple studios and edit suites, a nonlinear suite and high-end graphics. You will be responsible for system design, specification, installation, maintenance, and documentation. Experience with fiber optics, compressed video systems, satellite systems, Grass Valley Group 131, 250, DPM-700, GF-Halo 3, Series 7000, Sony BetaCam recorders and cameras highly desirable. We demand much from a Chief engineer but this is a GREAT facility and a GREAT place to work. Our current chief of ten years has left to be near family in the northwest. College of DuPage, located in Chicago's western suburbs, is the largest single-campus community college in the country, and is an equal opportunity employer.
Send Resumes to:
Audio, Radio & Television Services
College of DuPage
22nd & Lambert Road
Glen Ellyn, IL 60137-6599
Attn: David Gorski

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