A monthly newsletter by Society of Broadcast Engineers Chapter 48

September 1996

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The August Meeting
Upcoming Chapter 48 Meetings and Events
TFT Brings EAS Seminar to Denver
Hard Drives Made Easy - Part 4
Rocky Mtn. Film and Video Expo Comes to Denver
BE Shows Audio Vault in Denver
Clay's Corner
1996 SBE Certification Dates
WBA Mock FCC Inspection Program - Part 2
SBE EAS Primer Now Available
The Story of WAAK - Milwaukee's First Radio Station
A Technical Curiosity - A "True" 3-Way Splitter

The August Meeting

Once again Chapter 48 gathered at Coco's restaurant in Aurora for the monthly meeting. Due to some last minute changes, the program was switched from ISDN CODECs to a presentation on the Emergecy Alert System by Carl Goy of TFT. Carl was in Denver attending a conference regarding EAS for FEMA. Chapter chairman, Jack McKain, who is the state coordinator for EAS, and also attended the FEMA meeting, offered his insight into EAS. Carl gave an overview of the EAS system, followed by a demonstration of the TFT EAS 911. This was followed by a discussion of the benefits of some of the EAS equipment that is available from various manufacturers. For many of us, this was our first chance to get real "hands on" experience with EAS. Thanks again to Carl Goy of TFT and Patrick Connolly with Burst Communications for arranging this informative presentation on short notice.

Now hear this...we are looking for door prizes for our combined meeting with SMPTE and SCTE in October. If you have something you can donate to the chapter, you'll get a big thank you in this newsletter! Please contact Eric Schultz at KDVR TV31 at 595-3131 or Bill Harris at KXKL FM at 832-5665.

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Upcoming Chapter 48 Meetings and Events

Wednesday/Thursday September 18/19, 1996
Rocky Mountain Film and Video Expo - Holiday Inn DIA, I-70 and Chambers Road. Call (303) 771-2000 for more information

Thursday, October 17, 1996, 11am - 3pm, KUSA studios
The joint SBE/SMPTE/SCTE meeting will be held on October 17th at 11:00 am, at the KUSA studios, located at Speer and Logan in Denver. The tentative presentation schedule is as follows:

  Randy Brigham     Sony Digital Data Interface               11:00 - 11:45
  George Abe        ATM, Packetized video/audio transmission  11:45 - 12:30
  Lunch             Hosted by SCTE.SBE.SMPTE                  12:30 - 1:00
  Charles Kennamer  Testing of compressed signals             1:00  - 1:45
  Rich Rodriguez    The future of communications              1:45  - 2:30
  Leo Cirbo         FCC update                                2:30  - 3:00
  Myron Oliner      KUSA facility tour                        3:00  - 3:30

NOTE: This meeting will be catered, so you will need to R.S.V.P. if you plan to attend. Call Eric Schultz at KDVR-TV (303) 595-3131 or email under@dimensional.com by Monday, October 7th to R.S.V.P. Lunch will be provided by the SMPTE/SBE/SCTE. Admission is free to members, $10.00 to non - members. The meeting will include Chapter 48 officer nominations for 1996 - 1997.

November 20, 1996, Wednesday, 12 noon, Coco's Restaurant
Chapter Elections, EAS update (deadline is Jan. 1), Ennes foundation

December 18, 1996, Wednesday, 12 noon, KWGN studios
FCC's new inspection vehicle

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TFT Brings EAS Seminar to Denver

If you're like a lot of folks who need a lesson in how the new Emergency Alert System will work, here's a golden opportunity. The folks at TFT will be here on Wednesday, September 18 at Baby Doe's Restaurant, just off I-25 and Speer Boulevard, from 11:30 am to 2:00 pm. Bruce says the early birds will get hands on. They'll even pop for lunch! Join Bruce Vann from TFT for an in-depth look at EAS (and of course, the TFT system). For more information, call Bruce at TFT: 800 347-3383 ext 217.

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Hard Drives Made Easy - Part 4

Eric Schultz - Chapter 48

This month we'll conclude this series about hard drives with a look at the various flavors of the interface known as the Small Computer Systems Interface or SCSI (pronounced "scuzzy").

In the early 1980s, PC manufacturers were faced with the problem of interfacing a growing number of computer types to a growing number of computer peripherals. Computers needed to be able to talk to a plethora of peripherals, including hard disk drives, tape drives, CD-ROM drives and even optical scanners. Thus, SCSI was developed.

SCSI is a bus architecture, using a host adapter (often mistaken to be a controller) to interface between the computer and the various devices on the SCSI chain. The devices on the SCSI bus each have a controller built in. The host adapter doesn't do much more than pass data and instructions between the host computer and the SCSI bus. One important difference between IDE and SCSI interfaces is that the IDE interface card is just there to pass data from the computer's data bus to the IDE drive/controller combination. The SCSI host adapter card actually translates between the PC and SCSI busses. This separate bus allows for the connection of a large variety of peripherals. SCSI cables can be up to 6 meters in length, making it ideal for connecting large drive arrays, such as video servers. The IDE bus is not as robust, and IDE devices are typically internal to the PC.

SCSI actually has several advantages over IDE. You'll recall that only two IDE devices can be attached to each interface. Using Enhanced IDE, two adapters can be used, allowing four IDE devices in a PC. The original SCSI specification, now known as SCSI-1 or Narrow SCSI allowed the connection of eight devices, one of which is the host adapter. Each device on the SCSI bus has a unique address, 0 through 7. The bus is an 8-bit parallel bus, terminated at each end. Address conflicts and improperly terminated chains cause unpredictable behavior in the system, often causing users problems when installing SCSI devices. Although this is considered to be a drawback to SCSI systems, keep in mind that IDE devices must also be configured either as master or slave in order to work properly.

Since the first SCSI standard was approved in 1986, several descendants of SCSI-1 have emerged. As mentioned above, SCSI-1 allows the connection of 8 SCSI devices on an 8-bit wide bus. Any two devices on the bus can exchange data at 5 megabytes per second.

In order to improve SCSI-1, a new SCSI standard, SCSI-2 was later introduced. SCSI-2 offers increased data integrity and higher data transfer rates. By increasing the bus clock rate from 5 MHz to 10 MHz transfer rates of 10 MBps are possible. This is known as Fast SCSI. Transfer rates of 10 MBps are also possible by doubling the bus width from bits to 16 bits. This is called Wide SCSI. Wide SCSI adapters use a 68 pin connector instead of the 50 pin connector found on 8 bit SCSI chains. However, Wide SCSI host adapters come with both 68 and 50 pin connectors for backward compatibility. The increased bus width also allows the connection of 15 devices to the host adapter. Furthermore, Fast and Wide SCSI can be combined, resulting in a maximum transfer rate of 20 MBps.

Of course, SCSI does not end with SCSI-2. The newest flavor of SCSI, SCSI-3 is now hitting the consumer market. Currently, UltraSCSI is the latest and greatest parallel SCSI format. UltraSCSI doubles the Fast SCSI clock rate to 20MHz and uses the 16 bit wide data path of Wide SCSI. UltraSCSI, which is sometimes referred to as Fast-20 Wide SCSI, allows maximum transfer rates of 40 MBps.

Note that I mentioned that UltraSCSI is a parallel format. SCSI-3 also provides for the standardization of serial SCSI interconnects. The serial SCSI-3 architectures include Fibre Channel, Serial Standard Architecture, (SSA) and IEEE P1394. These new serial formats offer impressive transfer rates (hundreds of megabytes per second), lengthy connections using fiber optics, easy configuration, and true hot-swapping capabilities without the use of special connectors. Unfortunately, serial SCSI-3 formats are not backward compatible with SCSI-1 and SCSI-2 formats.

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Rocky Mtn. Film and Video Expo Comes to Denver

With low costs and professional capabilities, new media production capabilities have created new opportunities for businesses to develop powerful and innovative multimedia productions for a virtually unlimited number of uses.

For companies (and engineers) exploring in-house multimedia production, your research might lead you to explore the Rocky Mountain Film and Video Expo, Wednesday and Thursday, September 18 and 19 at the John Q. Hammons Convention Center at the Holiday Inn DIA, I-70 and Chambers road. There will be two full days of educational seminars and more than 120 manufacturers demonstrating the latest innovations, the show has become the definitive regional resource for information on all aspects of media-based communications.

Here's some tips on getting the most out of your visit to the Expo:

The show is co-sponsored by five regional suppliers to the professional film, video, audio and multimedia industry. They include Burst Communications, Inc., CEAVCO Audio Visual Company Inc., Davis Audio-Visual Inc., Film/Video Equipment Service Co., and Waxman's Industrial Network.

For more information, call Mark Cramer at Expo Masters (303) 771-2000.

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BE Shows Audio Vault in Denver

Broadcast Electronics is coming to town the third week of September, from the 18th to the 20th, demonstrating their Audio Vault system at the Holiday Inn hotel in downtown Denver. On hand will be the new BE southern area regional manager Rick Strage to meet and greet you. Reservations accepted for private viewing from 9 am to 5 pm. FAX 817-556-0729 with your station call/company name and number of attendees, or E-mail to VAULT@FLASH.NET.

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Clay's Corner

Chapter 16, Seattle

Featuring News, Rumors, And Views From Usually Reliable and Irrefutable Sources

Enco, one of the Radio Audio Network suppliers,has released a cost comparison of using their computer based audio delivery system vs. analog cart machines for a standard radio station, i.e., an Air Studio, News Room and two Production Rooms. Price for the computer system = $72K... for analog carts = $101+K. Who would have thought that you could replace all those tape machines with a computer system and have it cost less?

Pacific Recorders is NO MORE. The word RECORDING being an ancient term, PR&E is now Pacific Research and Engineering. And, they have gone public with trading taking place on the American Exchange. I guess recording evokes thoughts of vinyl, or acetate, or tape. With no one in the computer world ever using the word I guess it was time for the term to change. Ever ask someone to go RECORD A DISK? or MAKE A DUB OF A FLOPPY? Or RECORD THIS ON YOUR HARD DRIVE? Even though this is what they are doing (to us oldfolks) we can't use old terms to describe the process. That wouldn't be cool. But these old terms have a way of coming back. Like the FCC's use of the term WIRELESS. Oh, well.

What in the world is happening with DAB? First we learned that the lab tests of some of the in-band systems did not go well. Then we were told to look to the field tests in San Francisco. Then we learned that one of the major in- band proponents (USA Digital) was not coming to the party. EIA is apparently moving forward with plans for testing the ATT, Eureka and VOA/JPL systems.

Boys, boys, boys!!

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1996 SBE Certification Dates

Planning to become certified this year?

DATE: Nov. 8-18
LOCATION: Local Chapters

Contact Chapter 48 Certification Chairman Dave Sawyer at KHOW/KHIH Radio at 694-6300.

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WBA Mock Inspection Program - Part 2

Chris Cain - Chapter 24, Madison

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

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SBE EAS Primer Now Available

The 40 page, SBE EAS Primer is now available from the SBE National Office. The publication is a guide to the new Emergency Alert System and its implementation. The cost for SBE members is $25 and $30 for non-members. Call the SBE National Office at (317) 253-1640 to order.

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The Story of WAAK - Milwaukee's First Radio Station

In the early spring of 1922, the United States Commerce Department granted the Gimbels Department Store licenses to install and operate radio stations in Philadelphia and Milwaukee, assigning the call sign WIP to Philadelphia, but giving one of the first of the new four letter call signs, WAAK, to the Milwaukee store.

A wind-up record player stood in the studio for transcription concerts, along with the studio microphone. In those days, the carbon-button microphone was wired directly across the high voltage power supply of the transmitter, so to protect the announcing staff, Clarence suspended the microphone from a handsome brass birdcage stand supplied by the store.

Programming for WAAK was supplied by a local musician and producer named Raymond Mitchell, who promptly shanghaied Bates' assistant engineer, Daniel Gellerup (later to become Chief Engineer at WTMJ) to announce the programs. Getting talent for WAAK was simply a matter of scouring the local theaters and recital halls for visiting artists, and securing their (usually willing) cooperation.

In preparation for the first broadcasts at WAAK, Gimbels established "listening posts" throughout the store, where shoppers were invited to pause and listen to the programs on individual earphones. It is important to remember that the general public was not yet sold on the utility value of a broadcast receiver in the home - the very factor that WAAK was designed to address.

In any case, the first "official" broadcast over WAAK was presented at 7:30 p.m. Wednesday, April 26, 1922, on the only frequency authorized for domestic broadcasting: 360 meters, or about 830 kHz.

And what eventually became of WAAK?

The pathfinding Milwaukee station lasted less than a year. In the spring of 1923, new federal regulations mandated the installation of expensive wave- metering equipment at all radio stations. Since by that time there were three other stations on the air in Milwaukee, Gimbels decided to pull the plug on WAAK, thus ending their pioneering experiment in Milwaukee broadcasting.

--excerpted from "Once a Century," the annual publication of the Milwaukee Press Club, Volume 89, 1985. Original article by Terry Baun.

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A Technical Curiosity - A "True" 3-Way Splitter

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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Newsletter Committee

Bill Harris.......(303)756-4843 email: BHarris4@IX.netcom.com
Garneth M. Harris..(303)756-4843
Andre' Smith.......(303)871-4204 email: ansmith@du.edu

Views expressed herein do not necessarily reflect the official positions of the Society, its officers, or its members. We regret, but are not liable for, any omissions or errors. The Denver SBE Newsletter is published approximately twelve times per year. It is prepared with a combination of text and graphic data. Submission deadline is 10 days before the last day of each month. Other SBE chapters are permitted to use excerpts if attributed to the original authors, sources, and/or the Denver SBE Newsletter.