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SBE Certification Program Attains Recognition

June 12, 2003 Meeting Report

New SMPTE Officials Take Office

Random Radio Thoughts

DVB-S2 and MPEG-4

Taste Of NAB Road Show

Resume Service Is On-Line

Stay Connected - Renew Membership Today

A Petition For A Low Power Community Radio Service In The AM Expanded Band

Transmitter Crowbar Explained

Clay's Corner

The End User




July, 2003

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SBE Certification Program Attains Recognition

Washington - June 10, 2003 - The National Skills Standards Board (NSSB) was formed in response to the large number of industry certifications in the marketplace. NSSB Certification Recognition was designed to help users of certifications navigate through the maze of certifications by identifying those that meet high professional and technical standards for quality assurance. To receive recognition, a certification must undergo a comprehensive review to ensure that it meets specific quality requirements.

The Society of Broadcast Engineers Program of Certification offers several levels of certification for the broadcast industry. The program began in 1975 as an industry response to the reduction in FCC operator licensing. Since then, the program has grown to include a group of sequential certifications that cover traditional broadcast engineering skills and knowledge, as well as certifications for TV operators, radio operators and broadcast computer networking technologists.

While the broadcast industry has long accepted SBE Certification as a valid mark of an individual's skill, the SBE National Certification Committee has sought approvals from outside the broadcast industry to further the program's existing reputation.

On June 10, 2003, the NSSB granted its recognition of the following SBE certification levels:

  • Certified Broadcast Technologist (CBT)
  • Certified Broadcast Engineer (CBRE/CBTE)
  • Certified Senior Broadcast Engineer (CSRE/CSTE)
  • Certified Professional Broadcast Engineer (CPBE)
  • Certified Broadcast Networking Technologist (CBNT)
  • Certified Audio Engineer (CEA)
  • Certified Video Engineer (CEV)
  • Certified Television Operator (CTO)

"This achievement marks a significant peak for the Program of Certification," said Chriss Scherer, CSRE CBNT, chairman of the SBE National Certification Committee. "The SBE Certification Committee members-current and past members alike-devote a great deal of time and effort to the Program of Certification. This honor strengthens our belief in our own efforts and takes SBE certification to a higher standard of excellence."

Troy Pennington, CPBE CBNT, president of the SBE added, "I'm pleased that the SBE Certification Committee has pursued and obtained this important recognition for the various certification levels within the Program of Certification. We're proud of the significance that SBE certification holds in the broadcast industry, and this honor further proves the value and significance that SBE certification provides."

For more information on SBE certification, contact the Society of Broadcast Engineers at 317-846-9000 or

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June 12, 2003 Meeting Report

Starz Encore Group hosted our All-Day Technical conference on June 12th, 2003. Over 90 attendees were provided with insightful and informative presentations. The meeting led off with Mike Babbitt from Dolby Laboratories with a description of the Dolby E transport stream, the DTV environment, and an acoustic demonstration of the capabilities of "Dial-Norm". Scott Barella, Vice President of Engineering for the Burst Group gave us a primer on the ASI signal construct. Matt Klien, System Architect for Pinnacle Systems, provided a discussion on ASI, HD, and SD signal processing, storing, and playout in video servers. John McClusky of Tandberg discussed MPEG encoders for HD. Mark Corl, Director of Engineering, Systems and Architecture gave us an in-depth look at PSIP and the ATSC transmission scheme. Thanks to Tom Mikkelsen and Starz Encore for hosting the sessions; and our thanks to The Burst Group, Pinnacle Systems, Dolby Laboratories, Trivini Digital, and Tandberg Corporation for their financial sponsorship.

The June, 2003 Meeting
Scott Barella provides a primer on ASI

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New SMPTE Officials Take Office

From Rome Chelsi
Chairman, SMPTE Rocky Mountain Section

I would like to personally extend a welcome to our newly elected SMPTE board members:

Tom Mikkelsen - Starz Encore Group
Jim Schoedler - KRMA
Kim LeGate - Crown Media

As you probably know Tom, Jim, and Kim have been active in our local chapters and have been most gracious in providing venues and logistical help for our meetings. Tom was inducted as a SMPTE Fellow in 2002.

On behalf of our board, thanks for your desire to help out.

Since much of our SBE/SMPTE activities are managed by our ad-hoc committee, please feel free to suggest topics and or speakers for future sessions or ways to improve our chapters.

Hopefully everyone will make it to the Lookout Mountain Event on July 16th. See you there.

For a complete list of the Rocky Mountian SMPTE and Denver SBE Chapter 48 officials, see

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Random Radio Thoughts

Cris Alexander, CSRE
Crawford Broadcasting Company

Back in the 1960s and 1970s, we saw a lot of byproducts of the "space age" make their way into our lives. We all benefited from technology and products developed for the Apollo program. A similar thing happened when the PC was developed in the early 1980s. Everything from sprinkler controls to microwave ovens, VCRs and automobiles were given CPUs to (supposedly) make our lives easier. Another wave of technology byproducts is now washing over our society, spin-offs from developments for the Internet and computer networking. The broadcast industry stands to gain a lot from this technology.

At the spring NAB show, the products that most caught my eye were those that employed TCP/IP technology to achieve what we do every day better, faster and in a smaller space. One example is the Telos Livewire, which conveys multiple audio channels, control, program-associated data, VoIP telephone and computer data over a single piece of CAT-5 cable. Analog and digital audio I/O is made by means of small (1RU) interfaces. Control is achieved by means of a "studio engine" and "control surface" that looks and feels like a digital console. Other manufacturers were offering similar systems. The real beauty is that these operate over an infrastructure that is likely already in place, the studio Ethernet network.

This TCP/IP "revolution" is by no means limited to digital mixing and routing systems. I have noticed that more and more of the studio and transmitter peripherals that we purchase are equipped with a network jack on the back. Many of these have built-in web servers that allow configuration and control of the device. The chief engineer can sit at his desk and adjust the parameters on the transmitter audio processor, for example, in a controlled listening environment and away from all the noise of the transmitter blowers.

As we move forward in our expanding implementation of the Motorola Canopy system throughout Crawford's Denver cluster, we continue to find more and more ways to take advantage of the newly available technology. One jewel that we recently discovered is the Broadcast Tools DSC-32 digital serial controller. This device provides 32 contact closures over an RS-232 connection. Pull down an input on one end and the open collector or type-A contact closes on the other end. Connect this to another gem, the BT SP-1 RS-232-to-TCP/IP converter and you can do all this over an Internet or Ethernet connection. With the Canopy providing a 10 mb TCP/IP pipe from the studio to each of our sites (and from site to site), we can convey any contact closure or combination of closures in either direction. The possibilities are endless. We can convey relay closures from remotely-located satellite receivers back to the studio. We can convey real-time status from transmitter or studio to the other end, and we can control audio switchers, automation, even environmental controls remotely. The SP-1 will even allow us to connect our RS-232-based remote control systems without dedicated lines or subcarriers.

Another discovery we have made is the CM-20 module for the Harris Intraplex. The CM-20 allows the Intraplex to operate over a TCP/IP connection. Here in Denver we will feed audio to all our transmitter sites via Intraplex and TCP/IP over the Canopy. Between Denver and Colorado Springs, we will feed via DSL at a fraction of what we are currently paying for a dedicated inter-city T1 line.

Once you start down this road, one possibility leads to another. It almost boggles the mind. In addition to streaming audio and conveying control and telemetry signals, we can eliminate the transmitter site telephone line, replacing it with VoIP telephony, in essence making the transmitter site telephone a station on the studio/office PBX. Manufacturers can log into the web servers in our equipment at the studio and transmitter and help us troubleshoot. We can put web cameras at our remote sites and keep an eye on things. I'm sure that you've already thought of a few more. Hey you remote control manufacturers... how about a web-server based R/C engine? Transmitter manufacturers... how about putting secure web servers in your transmitters and exciters? Modulation monitors, antenna monitors, satellite receivers, generators, HVAC controls... the list is endless. I'm holding out for a CAT-5 isocoil for AM towers.

There's no doubt about it, we're entering a new age in broadcast technology. We can do more with less. In many ways that's a good thing, and in some ways it may not be so good. Much of that depends on how we use the available technology. More than ever before, it's up to us, the engineers, to craft and design the world we work in. Things have been relatively quiet on the Denver radio front of late. Most of the folks I have talked to are focusing on getting summer maintenance done at transmitter sites. Indeed at many sites, the season for that sort of thing is quite short.

We have heard that the folks over at Entercom are in the middle of a studio buildout and move. You might recall that they were victims of a roof collapse during the big storm last March. Roof leaks have reportedly plagued their studios in recent months. The pressure is on to move and move quickly. I don't have a lot of details because John Burnell and Mark Smith are understandably too busy with the project to stop and talk about it. We hope to have the whole story for you next month (and hope the project will be mostly wrapped up by then).

Jo-Mor Communications was recently granted a construction permit to relocate KJME from the present site at Denver Drywall (Zuni at Dartmouth) to the KLZ site (82nd and York). The plan is to diplex the KJME non-directional operation into the east tower at KLZ. A backup system is also planned that will allow diplexing into the west tower. KLZ's phasing and coupling system will allow ND operation off either tower for emergency or maintenance. The KJME operation will follow suit so that tower maintenance can take place without either station going off the air. Kintronic Laboratories will provide the diplexer. The transmitter building will be a prefabricated (cellular-type) structure and it will be located near the KLZ transmitter building. KJME will operate with 1.3 kW day and 59 watts night, the power reduction from the present 5 kW day/139 watts night resulting from the efficiency of the 225-degree radiators at KLZ. They call that "efficiency," but it doesn't look as good on the letterhead!

If you have news you would like to share with the Denver radio community, email me at See you at the picnic!

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DVB-S2 and MPEG-4

By Doug Greene
VP Technical Operations
Jones Media Networks, Inc.

Two new technologies could provide a multichannel operators with the ability of delivering as much as 60% or more channels than existing transmission systems. The two technologies 1) a channel coding technique called "Digital Video Broadcasting-Satellite 2" or (DVB-S2) based on 8PSK modulation transmission, and 2) a newer source code for video compression called "MPEG-4 part 10" or H.264 Advanced Video Coding (AVC).

The proposed DVB-2S specification allows for 3 bits per symbol using 8PSK modulation at approximately 80 Mbits/s information rate versus the current 2 bit per symbol QPSK at approximately 50 Mbits/s information rate on a satellite transponders. The current forward error correction method used for QPSK RSV (Reed Solomon Viterbi) is not suitable for the symbol enriched 8PSK modulation scheme and results in a poor bit error rate when delivering to existing size earth stations deployed by cable operations. Therefore, 8PSK modulation must use newer, robust FEC codes, such as turbo code or low density parity check (LDPC). The DVB technical group has recently voted against the use of turbo code and is now leaning towards the acceptance of LDPC as the new FEC code for the DVB-2S standard. Whether or not the newer DVB-S2 standard will be backward compatible with the current DVB-S specification remains to be seen. Having DVB-S2 backward compatible with DVB-S, such as the MPEG profiles and levels, would no doubt make it easier and possibly less expensive to deploy it in the future by satellite and cable operators. Final adoption of DVB-S2 specification is expected sometime this summer with chip manufacturers providing silicon product several months later - probably in early or mid 2004.

In addition to the increase of transmission bandwidth, such as DVB-S2, improvement can also be had with newer compression technologies, such as MPEG-4 part 10 or H.264 AVC. As much as a 40% to 50% increase in compression rates can be achieved over current MPEG-2 compression rates. For example, a 2 to 3 Mbits/s MPEG-2 stream could be compressed using a H.264 encoder/decoder at an information rate of 1.25 to 1.5 Mbits/s, corresponding to a DVD-quality picture via broadcast. It appears that H.264 AVC could be winning acceptance, especially in the DVB area. The adoption of the H.264 AVC is excepted this summer.

Keep in mind that all these standards still require chipmakers to produce silicon that can be used in set-tops. Both these technologies are going to require some time to implement onto silicon, but should be available as by mid to late 2004. Whether or not multichannel operations will take the plunge to update their transmission system using these technologies or others like it is hard to say. With the deployment of HDTV, VOD, VOIP, data services, and expanded digital channels, the multichannel operator may have no choice but to deploy these bandwidth efficient technologies in order to make better use of their limited bandwidth.

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Taste Of NAB Road Show

From Eddie Hernandez

KBDI will be hosting the "A Taste of NAB Road Show 2003" on Wednesday July 23rd from 11a to 3p. We are currently looking for a sponsor if you have any suggestions. There will be refreshments. The link is below for more information. Please inform SBE and SMPTE members and anyone who would be interested.

The Road Show - A Taste of NAB 2003


Eddie Hernandez Sr.
Chief Engineer
Phone (303)-296-1212 ext.251
Fax (303) 296-6650

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Resume Service Is On-Line

The SBE Resume Service is now online at ! With increased visibility and ease of use, the Resume Service is the perfect companion to JobsOnline for SBE members searching for new positions and for employers searching for the right candidates. At no cost, SBE members complete a questionnaire and send the national office copies of their resumes. This information is used to compile an anonymous profile that is posted (not the resume) on the SBE website for employers to browse. Employers interested in one or more profiles will contact the national office and pay a small fee to access the actual resumes.

SBE Members may use this service and any broadcast related employer may participate. For more information Contact Angel D. Bates at, 317-846-9000 or go to

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Stay Connected - Renew Membership Today

Members who not yet renewed can still do so and not miss out on valuable member benefits like the The SBE SIGNAL, discounts on publications and certification, access to SBE JobsOnline, Resume Service or life, health or business insurance. If you need a new form, call or e-mail Angel Bates at the SBE National Office at (317) 846-9000 or

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A Petition For A Low Power Community Radio Service In The AM Expanded Band

Press Release

Suggesting that neighborhood and community broadcast voices may be the most genuine broadcasters, Fred Baumgartner, a long-time broadcast engineer, proposes a low power service in the expanded portion of the AM band. Fred indicates that the proposal is based on a series of inputs from various groups, engineers, and individuals; and his best effort to find the middle ground.

The proposal is for a service with as much as 100-watts on the 10 AM channels from 1610 through 1700 kHz. The petition asks for an easy and affordable application process based on simple mileage separations, and asks for strict rules of use to guarantee that the spectrum granted is used to the community's best interest, and avoids the issues and distractions that have surrounded previous low power services.

The choice of the extended band is the perfect location for a low power community service, as receivers are available, and the potential for interference at the requested power and antenna limitations is nearly nothing. No other spectrum offers the same opportunity.

If adopted, the tender would create a spectrum grant where a typical community might have as many as six licensees sharing time on three frequencies, covering a few miles. The proposed service is constructed with minimum and maximum hours of operation that all but require two broadcasters to share each frequency, facilitating diversity. The rules also prohibit the ownership of more than one station, preventing a range of potential abuses.

The petition provides heavy protection for full power extended band broadcasters, but no protection for one LPAM broadcaster and another. The tender encourages the sharing of facilities, frequencies and resources in a community.

Rather than an involved technical application process, the proposal defines maximum antenna system size and requires type-accepted transmitters with integral limits on out-of-band emissions, frequency, and power level. This process is designed to allow application for a license without the expense of consulting engineers, or other unnecessary technical complexities.

The scheme permits LPAM (low power AM) broadcasters to support their operations with the sale of commercial time, and underwriting, but puts limits automated, network, and out-of-market content, as well as the hours of operation. The LPAM AM proposal requires hands-on-broadcasting.

The petitioner believes that if an LPAM service is granted with the suggested rules of use, a plethora of community stations will take to the air, and a valuable gap in broadcasting, truly neighborhood and community broadcasting, will be filled.

Community radio has been a contentious topic for some time. Broadcasters fear interference and competition from any serious service. Part 15 operation at very low powers is inadequate to serve any real public need. Without a legitimate means of broadcasting, pirates take to the air with self-justification.

Low Power FM has been authorized, however the rules of use often have made the existing services largely impractical and inaccessible to the people who would best serve and be served by neighborhood radio. LPFM technical requirements make getting a license a lengthy and expensive process beyond the resources and knowledge base of those not already involved in commercial broadcasting. Further, current FCC policy often permits enterprises to apply for multiple licenses, blocking out the very potential broadcasters the service was designed to support. In some cases, applicants even vie to assemble a series of low-power facilities, in effect creating a full power like service. FCC regulations may also serve to inhibit fund raising, and discourage sharing of frequencies, live operations, and limited time operation.

LPAM in the expanded band proposes to provide the missing neighborhood owned, and operated, community centered broadcast service.

Petition To The Federal Communications Commission
For Allocation of Secondary Broadcast Service on 1610-1700 kHz


The Petitioner is in favor of a "neighborhood" Broadcasting service that has sufficient regulatory safeguards to assure compatible spectrum use, with a licensing and construction process that is not unnecessarily burdensome, and appropriate for the limited use of the spectrum proposed, by neighborhood or community entities with limited resources.

The Petitioner has gathered comments from several groups and individuals interested in LPAM, often contradictory, and has considered these comments, and focused on what the petitioner considers to be a practical and useful service. The petition represents the petitioner's and selected council's advice and opinion.

This petition seeks authorization of a service allocation in spectrum between 1610 and 1700 kHz. This spectrum has desirable propagation characteristics (which is to say limited), and the current FCC licensing scheme provides opportunities between licensed regional stations suitable for neighborhood operation. This petition proposes a secondary service that provides a minimum of interference to existing and proposed full-power stations, and maximum utility for neighborhoods and rural communities desiring a limited broadcasting outlet.

Further, the proposal asks for rules of use that encourage diversity, and community service, yet permit the new service enough coverage and flexible enough rules of use to be useful and self supporting.


This petition requests specific technical rules, some distinctly different from current AM licensing:

1. This petition requests that all Low-Power-Amplitude-Modulation (LPAM) stations be licensed by the FCC.

2. The petitioner suggests that 100-Watt LPAM licenses should be granted only to applicants where the proposed location is 225-miles from an operating co-channel station, and more than 15-miles from any co-channel TIS (Traveler Information Service) transmitter, and 150-miles from any first-adjacent station, and 50-miles from any second-adjacent station; provided they are located in rural areas where there are not villages, cities, or towns within 5-miles of the transmitter with a combined population of more than 20,000 in the 2000 census.

3. The petitioner suggests that 30-Watt LPAM licenses should be granted to applicants where the proposed location is 185-miles from an operating co-channel station, and more than 10-miles from any co-channel TIS service transmitter, and 110-miles from any first-adjacent station, and 50-miles from any second-adjacent station, or the in locations where there are villages, cities, or towns within 5-miles of the transmitter with a combined population of more than 20,000 in the 2000 census. 30-Watt LPAM licenses may request a waiver of mileage separation from the licensee of any short-spaced broadcast station or TIS service, and may pay reasonable fees or grant items or services of reasonable value for the granting of such a waiver. If the waiver is granted, the license should be approved.

4. The petitioner suggests that LPAM licenses should be granted without regard to the existence of, or interference potential to other LPAM stations. LPAM stations with an interference issue should cooperate to schedule operation or share transmission facilities in such a manner as to reduce interference. Any dispute should be resolved through a mediation process, or a voluntary frequency coordination effort. Communities should be permitted to mediate the use of LPAM stations within their boundaries, if they desire to establish such a function within the community's government.

5. The petitioner suggests that LPAM antennas should be of either a single conducting vertical element (no helical winding, loading coils or other devices) not to exceed 40-feet in height, nor more than 4-inches in diameter. Horizontal radiating elements may be used provided the combine length of the longest horizontal element plus any vertical element must not exceed 40-feet. The ground and antenna connections must be less than 2-feet in length from the antenna-tuning unit to the radiating element and ground connection.

6. The petitioner suggests that alternately, a center feed balanced feed wire dipole antenna, not to exceed 80-feet in length (40-feet on each end) may be used. A ground system may not be part of the RF radiation system of the dipole. No more than 20-feet of balanced feed line may be used to connect the dipole to the antenna-tuning unit.

7. The petitioner suggests that only type approved transmitters, with 50-ohm calibrated outputs for the licensed power level and frequency, certified by the provider to be within +/- 5% of all power and modulation specifications, and +/- 15 Hz of the carrier frequency specification should be permitted. Further, type approved transmitters should include an audio limiter that restrains modulation between the range of -95% and + 125%, and restrains sidebands to -10 dB at 10 kHz, and -20 dB at 15 kHz, and -55 dB for all spurious emissions outside of 20 kHz of the carrier.

8. The petitioner suggests that regulations should permit an external or internal passive antenna-matching network, external audio processing, and internal or external calibrated modulation monitoring and display.

9. The petitioner suggests that regulations should prohibit any active components, in particular amplification, between the type approved transmitter and antenna, and any directional, or antenna radiation enhancement device or construction designed to improve performance beyond the antenna provided for. Transmission line between the transmitter and antenna-tuning unit should not radiate. Placing the transmitter and antenna-tuning unit at the feed point of the antenna is recommended. Further, fencing (or other means) should protect the RF radiating components from access by unauthorized individuals (feed point voltages are quite high in these configurations).

10. The petitioner requests the assignment of call letters similar to broadcast stations, but recognizably different, i.e, "K1650ABC," or the use of N and or A prefixes as in "AABC."

11. The petitioner suggests that power levels remain the same day and night.


1. The petitioner suggests that a licensee may be an individual, organization or corporation.

2. The petitioner suggests that a licensed LPAM entity may not own, operate, program (with the exception of occasional guest appearances), or control in any way more than one LPAM.

3. The petitioner suggests that no licensed broadcast station, nor any entity with broadcast ownership, excluding minority stock ownership, may be the licensee or a party in the licensed entity operating an LPAM station.

4. The petitioner suggests LPAM entities be allowed to share time on a single transmitter, and be permitted to contribute resources to purchase, construct, and maintain a common LPAM transmitter facility. LPAM entities should not be permitted to share studios, staffs, or other resources.

5. The petitioner suggests that the LPAM license term should be for 5-years, and should be renewable.

6. The petitioner suggests technical operating parameters should be identical to broadcast stations, and include the option of utilizing AM-stereo or IBOC, operation, and all other ancillary services typical of AM broadcast stations.


This petition requests particular rules of use to encourage a legitimate and useful service, and serve a particular purpose. To that end, we propose the following rules of use and constraints:

1. The petitioner suggests that licensed LPAM stations should be required to provide no less than 8-hours of service nor permitted to broadcast more than 85-hours for each licensed entity, in a given week.

2. The petitioner suggests that licensed LPAM stations should be required to be manned by an on-the-air operator in a live manner no less than 60% of each operating entities weekly operating schedule. No more than 40% of the schedule should be unmanned, or automated, or long form recording, or the rebroadcasting of long form "network" programming.

3. The petitioner suggests that licensed LPAM stations should be required to have a working telephone within reach of the operator, able to be broadcast live. The telephone number and mailing address should be identified hourly.

4. The petitioner suggests that LAPM stations should be required to posses an EAS receiver, configured to automatically rebroadcast appropriate EAS messages live and instantly. The EAS equipment may be consumer, non-type accepted, and need not log events; but must be tested and certified as operational and actively in service, by the licensed entity.

5. The petitioner suggests that licensed LPAM stations should be allowed to broadcast commercials or sponsorship announcements, live and recorded religious, sports, political and community events. LPAM entities should be responsible for obtaining any rights, and paying any royalties required for the acquisition of program content as a condition of license.

6. The petitioner suggests that licensed LPAM stations should be required to keep program logs or 90-days or off-air recordings, and should be required to comply with all FCC content regulations, including any political requirements, prohibitions on obscenity, and public safety concerns.

7. The petitioner suggests that licensed LPAM stations should not be permitted to rebroadcast any broadcast station's live or delayed sustaining program for more than 15-percent of the LPAM's programming schedule in any given week, except when the rebroadcast programming provides information of a public safety nature. No broadcast station should be permitted to rebroadcast any LPAM's programming except when the rebroadcast programming provides information of a public safety nature, or serves an occasional and peculiar news interest.

8. The petitioner suggests that licensed LPAM stations should be limited to re-broadcast network provided programming for no more than 25-percent of the LPAM's weekly programming, except to provide for the occasional public safety concern.

9. The petitioner suggests that LPAMs be prohibited from accepting paid or other programming from broadcast stations, or any brokerage arrangements with any full-power broadcast station. However, LPAM's should be permitted to raise funds through sponsorship, paid commercials and programs.


The proposed LPAM service is designed to provide an easy to license, and easy and economical to construct neighborhood broadcast facilities with approximately 1 to 5 miles of useful coverage. The reliance on mileage separations from full-power stations rather than calculated or measured signal levels simplifies the licensing process and serves the more reasonable purpose of providing ample protection to the service area of the full-power stations. The choice of type approved packaged transmission systems makes construction possible for most anyone, without engineering expense, and assures a uniform product. The choice of frequency is to take advantage of the shorter antenna requirements, shorter ground wave, and current licensing practices that results in widely spaced, largely omni-directional full-power stations, with limited areas of overlap.

The petitioner asks specifically for a service available to those who cannot afford to compete with the commercial conglomerates for stations, and who are unlikely to use tools of mass program distribution for profit.

The petitioner considers the value of small pockets of useful neighborhood and community service, in particular in rural and urban communities, to far outweigh any disadvantage the resulting zones of interference might create, where the petitioner contends no useful service now exists in any case.

The choice of antenna and power limits results in a fairly inefficient installation, but is practical to construct and inherently limits any interference to full-power stations. While daytime operation clearly presents no meaningful interference threat, the combined LPAM transmitters provide a theoretical (albeit insignificant) nighttime increase in interference to full-time stations. The petitioner contends that the power levels should remain fixed during nighttime operation, suggesting that the public good provided by LPAM exceeds the expected increase in noise level to the full-power stations. Given the increasing noise levels from electronic and electrical devices, the impact of LPAMs is arguably negligible.

It is the petitioner's contention that broadcasting ownership and control has become concentrated in large financially motivated enterprises and larger cities. The petitioners believe that community and or neighborhood voices are important and should be considered in spectrum allocation. The petitioner believes that the opportunity exists to create an LPAM service, and the potential positive returns outweigh the potential costs and negatives.

The petitioner believe that such an LPAM service will permit community and neighborhood churches, schools, public service organizations, governmental, and private entities access to the airwaves.

The petitioner recognizes that there are opportunities for abuse. LPAM stations may interfere with each other, content may be weird or otherwise questionable, disputes over access times will exist. I consider these acceptable negatives. LPAM as proposed places responsibility on the neighborhoods and communities served, rather than the Federal government. As such, LPAM will work as well as the community or neighborhood it serves desires.

We also recognize that in the great scheme of things, LPAM is a minor effort with a potentially significant impact on the lives and well being of a significant number of the residents of this nation. We respectfully request that this proposal not be over-thought, nor any special interest group be permitted to pervert a proposal that involves very limited spectrum in a very limited manner.


The FCC recognizes an acceptable field intensity for Traveler Information Stations (TIS) operating in the proposed frequency range of 2.5 mV/m at one-mile. From the TIS experience, we know that the 49-foot TIS antenna, probably helically wound, and typical ground system, with 20-Watt transmitter is not a particularly efficient system. The purpose of this proposal was to define a system that could be built in most locations with a minimum of zoning considerations, and limited efficiency, similar to the TIS installation.

Following the research of Brown, Lewis, and Epstein, as reported by LaPort, the requested 27-degree antenna with 100, 50-degree radials, from the charts, results in 59 mV/m at 1 km for 100-Watts and at 30-Watts results in a field of 18 mV/m at 1 km.

In practice, the field strengths are certainly somewhere between the TIS experience, and the work by Brown, Lewis, and Epstein. Nonetheless, lets consider the 59 mV/m at 1 km to be the worst-case (from an interference perspective) analysis. This places the 0.025 mV/m contour at 45 km with the best ground conductivity of 30.

On the part of the protected station, lets assume the full 10 kW as permitted is in use, and a ground conductivity of 30 with a full wave antenna and proper ground system as permitted. This places the 0.5 mV/m protected contour at 142 km.

Given this, the minimum separation required for the co-channel is 187 km, or 117 miles. The request asks for 225 miles (363 km). Even a hundred LPAM stations all operating 225 miles from the primary station cannot produce any meaningful interference into the 0.5 mV/m contour of the primary station.

The proposal is tighter on adjacent channel interference.

Likewise, it is unlikely that any proposed antenna is capable of delivering a significant skywave signal.

The bottom line is that we have been unable to come up with any scenario where an LPAM built as prescribed in the proposed rules, and following the simple mileage separation scheme proposed, fails to protect the primary station well beyond any current standard. There is a considerable range for LPAM installations to be both useful as community services, without causing interference.

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Transmitter Crowbar Explained

By Vicki W. Kipp
Compliments of Chapter 24 - Madison WI

Define Crowbar
Although I was familiar with a crowbar as a device for prying, I wasn't as familiar with the transmitter crowbar. Inquiries about the crowbar yielded various definitions- all correct, but not all relevant to the transmitter. The brooding band Crowbar, a sludge metal band from the 1990s, played the club circuit and not the transmitter circuit. Likewise, the Canadian blues-rock band Crowbar was well known in the 1970s, but of no use in a transmitter. The practical crowbar tool, a flat metal lever with a chiseled end, is helpful for prying but should not be used with a transmitter.

As it relates to a transmitter, the crowbar is named for the concept of a grounded metal bar touching all the transmitter terminals when a high voltage surge occurs. Transmitters running at extremely high voltage need to be shut down immediately in the event of a component problem or voltage surge to prevent damage to the transmitter. Upon a surge, the crowbar swiftly diverts the voltage to ground and drains voltage from the transmitter's capacitor bank. The crowbar isn't really a metal bar at all. In the case of my employer's Comark IOT and Acrodyne Diacrode transmitters, the crowbar is a small gas-filled tube.

Two generations of shunt crowbars have been developed. The triggered spark gap is a first generation crowbar. This crowbar works well enough when it works. Unfortunately, the triggered spark gap crowbar is not infallible and ages each time it fires. The second-generation crowbar is the hydrogen thyratron. Operating ten times faster than a triggered spark gap crowbar, the thyratron has an active cathode and reservoir that will gradually break down. The hydrogen thyratron is considered the more elaborate crowbar because it demands isolated high voltage power and has many components floating at high voltage levels.

Not A Fuse
A crowbar is different than a fuse because a fuse creates an open circuit in the event of a voltage surge, while a crowbar creates a controlled short when a voltage surge occurs. The crowbar shorts high voltage to ground by discharging the capacitor bank when a voltage surge occurs.

The crowbar device is unique to Inductive Output Tube (IOT) transmitters. Klystron tube transmitters and solid-state transmitters don't use a crowbar. IOT transmitters require a crowbar because the tubes are very small and if gas builds up inside the tube, there is not enough room for the tube to diffuse the accumulation. If not for the crowbar, the amassing gas would seriously harm the IOT tube. The IOT would create a voltage surge that could melt transmitter components if not immediately shorted to ground.

Crowbar Firing
When the crowbar shorts, there is a violent reaction. The crowbar is draining 32 kV (or more) of electricity to ground in less than 10 milliseconds. This rapid shunting of extremely high voltage strains the equipment. To test that their crowbar is working properly, engineers can run a 40-gage wire (the diameter of a human hair) from the transmitter power supply to ground. For correct operation, the crowbar must short the high voltage to ground before the 40-gage wire burns up.

When the crowbar shorts high-voltage to ground, this is referred to as crowbar "firing." A typical crowbar should be able to tolerate being fired about 50 times before needing to be replaced. The crowbar is connected to a relay that tells the transmitter to attempt to restart after the crowbar finishes shorting the high voltage. If the transmitter does not restart successful before the crowbar has fired three times, then the transmitter tube will be shut down entirely. If the tube hasn't overcome the problem within three attempts, it is likely that there is a very serious problem that could damage the tube if it continues to operate while impaired.

Days Numbered
As the energy-efficient Multi-Stage Depressed Collector (MSDC) transmitter tube catches on for use in digital transmission, the crowbar is being excluded from these new transmitters.

Crowbar firing is stressful for a transmitter. Additionally, a crowbar is a common source of problems in IOT transmitters. Excluding the crowbar will increase transmitter reliability-at least that's what MSDC transmitter vendors claim. Not having a crowbar spares the transmitter from extended periods of downtime when the crowbar fires and then attempts to restart the tube.

Several vendors are using fast switching power supplies that create an open circuit in the high voltage power circuit in a matter of nanoseconds- versus the milliseconds a crowbar needs to react- when a problem occurs. The fast acting power supplies pass the 40-gage wire test, and make the crowbar unnecessary.

Information for this article came from: Dave Schilz of WHA-TV; Thales Broadcast & Multimedia; ARRL Extra Class License Manual.

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Clay's Corner

Featuring News, Rumors and Views
From Usually Reliable and Irrefutable Sources
June 2003 Issue

By Clay Freinwald

Boy! Where has this year gone? As I sit here writing this column for June I can't help but reflect on the fact that this is the 6th month... and that's... half-way.

Lots going on in our industry in our area, as usual. The big news of this past month has to be the decision by Fisher to concentrate on their core business, in this case, broadcasting, as opposed to selling out to what could have been some large conglomerate. Personally, I think that this is great. Nice to have some hometown ownership in our industry. Certainly the folks that work at the 'Fisher-Factory' have got to be pleased as well. Nothing is more undermining than the knowledge that the company that you work for might be sold; trust me, it's very hard to keep the spirit during these times. I wish them well. Fisher did get a piece of good news with the announcement that Adhost had inked a deal to move into 8,000 feet of Fisher Plaza.

Meanwhile things are not well over at KCTS. According to published reports there may be as much as 25% of the staff hitting the streets due to some rather severe financial issues. The reasons for this change are varied and certainly beyond the scope of this publication, but it looks like a number of factors are involved. I found it interesting that Ch 9 has hired the former president of Bates Technical College in Tacoma (Home of KBTC) to try and get the Seattle station back on track.

Down the Sound, in Tacoma, things are apparently much better with KBTC where they report that they are not in financial peril. If you recall, KBTC recently purchased the old KSTW plant. I noted an article in a recent issue of the News Tribune about KBTC--a picture of Jelson Dominquez, one of their Engineers.

In early May our area ran its first Amber Alert. In this case involving some missing girls who were later found. Like all events of this nature there was some grumbling about the basis of the alert. We need to remember a couple of things: 1) Amber Alerts are initiated by a Law Enforcement Agency (in this case the Kent Police Dept); 2) Amber Alerts are NOT initiated by those overseeing the EAS program (EAS is only the conduit); 3) There are a lot of refinements to the Amber program in the works, i.e., it's going to get better. And finally, 4) ALL stations should be airing these messages. I know for sure that some stations received the Amber Alert message but elected, for various reasons, not to air them. Granted, Amber falls into the 'voluntary' side of EAS (not FCC required) but I feel that there is a moral obligation for all stations to participate in getting these messages out to the public. Certainly if Amber is going to be able to save lives, we are all going to have to participate. I would hope that at perhaps our Electronic Expo in October that we might be able to have a meeting where Amber could be discussed in great detail. This would be a meeting where GMs and PDs could come to better understand what's involved here. Certainly there will be more 'coming-down' on Amber as a result of the President's signing of the Amber Bill. Under this bill we can look for more uniform standards for the use of Amber Alerts. Some have been suggesting that Amber be made a mandatory relay. Stay tuned!

Remember the past Chapter Meeting where we met at Andy's Diner and heard a presentation about the 802.11b WiFi Internet service system in Seattle? According to a recent study published in the Washington Post there are now over 4,000 such operations around the country.

From the 'interesting but not likely' dept. On March 26th the Citizens Broadcast Band Discussion Group filed with the FCC a petition asking for a NOI on the establishment of a NEW Broadcast Band (Just when you are up to your ears in IBOC and DTV).

Congratulations to Jim Hatfield on his retirement. Was talking with Jack Barnes at Fisher the other day. He was telling me that he is counting the days until retirement comes his way. Then there are those that are starting to ask ME when I am going to retire. Let me put it this way. Looking at my 401K... it will be some time until I will be able to join that club. Considering that list of Honey-Do's that await any man at retirement time... maybe working is not such a bad deal... especially if you enjoy what you are doing.

Speaking of what I have been doing. It's construction time around the Entercom radio-factory. With lotsa boxes of new gizmo's being hauled up to West Tiger for our big HD-Radio project my days are pretty much consumed with that chore.

I understand that the FCC is being hammered with FM translator applications . . . apparently to the point that their computer system for dealing with such things was under-sized. Projecting ahead we should find the FM band filled to the brim with signals, many of them on the outskirts of the metro. Seems that a lot of these 'broadcasters' are actually what are termed 'Satellators' . . . meaning a low-powered FM transmitter that's being fed with programming distributed via satellite. If you listen now around the lower part of the FM band you will find a number of these. If you are tracking call letters in the area... here's a new one. KOWA-LP for Olympia.

For years the spectrum of choice for wireless mics, etc., has been un-used UHF TV channels. If you have not been keeping track, here is a quick list of the Analog TV channels in our area: 4, 5, 7, 9, 11, 13, 16, 20, 22, 28, 33, 45, 51, 56. My quick count tells me that this is 14 stations...and when you consider that each one of these has a companion UHF DT operation licensed . . . this means we have approximately 22 operations on UHF that need to be considered. For our Coordination Team, working with events at Seahawks stadium, this means a whole lot less spectrum for wireless 'things.' I guess in some areas, like L.A., there are only 2 or 3 channels left for 'other' things.

Received a call from Ron Hansen the other day. He was telling me that the group that he works for in Yakima is looking for a cluster chief. This position is open following the retirement of Andy Thompson last year. If you are interested in the chief's job at this 6-station cluster, contact Ron at Clear Channel - Yakima for more information.

Understand that George Bisso ( Sandusky) was in the hospital for some surgery in early May. Hope all is well, George, and you are back on your feet.

Got a catalog in the Sunday paper from Radio shack . . . guess what?They are advertising TV Antennas! . . . and they are 'HDTV Ready.' The ad mentioned two models, one for city and suburbs and the other for rural areas. No mention of the type of feed-line.

On April 5th, Kahn Communications (think AM Stereo) released an announcement of the development of new technology that will restore AM broadcasting to '15 kHz stereo fidelity' by the use of digital processing. They call the system Compatible AM Digital or 'Cam-D.' The release claims a couple of things that are bound to stir some interest as Ibiqity wrestles with how to make their IBOC system work on AM at night. According to Kahn, the system will not increase adjacent or co-channel interference and therefore will be able to be used day or night. The Ibiquity system appears to be in trouble with many claiming that its use of the station's adjacent channels for digital carriers causes considerable interference issues with stations great distances away due to sky-wave at night. AM Broadcasters are likely to not jump on the HD Radio bandwagon until all this is sorted out.

Remember the name Jack Williams? Jack, for many years, was the name associated with Pacific Recorders, makers of a very popular line of audio consoles. A while back PR&E was purchased by Harris. Jack has now resurfaced and is working with Sierra, a maker of popular audio routers, who has now entered the audio console market with a new line. Those that were at NAB got to see just what they have been up to, first hand.

FCC honcho, Powell, has been making a number of comments about cross-ownership of newspaper and broadcast stations. (The last one in this area was likely the KTNT-FM-FM-TV operation in Tacoma owned then by the Tacoma Tribune.) It's going to be interesting how this turns out and what impact it might have. If what the Seattle Times has been saying of late is true, I would guess that we don't have to worry about them buying a cluster of broadcast stations in Seattle.

Speaking of ownerships. I should note that one ownership in our area is now 30 years old. I am speaking of KMTT that was purchased by Entercom back in 1973. In today's terms, this is a long time ago.

While I am looking back, I received a call from John Forbes the other night. He did some digging as a result of a comment in a recent column. I started writing this column back in October or November of 1986. Golly, that's 17 years ! Pretty long by most standards.

If you followed the efforts of KRKO to erect new towers in the Sno-Valley you noted that one of the arguments used was that the towers would lead to killing birds. This is not just a local issue. Recently the NAB joined some other organizations fighting efforts by environmental groups trying to get the FCC to take actions to prevent deaths of migratory birds from communications towers. Chairman Powell has responded that the FCC will indeed adopt an NOI re. the matter. All I can say is what's next?

From the 'It's about time' dept . . . The FCC and FAA are actually going to start communicating 'electronically' regarding airspace issues involving applications for facilities. This new system replaces the old paper copy system we all came to ____. (You fill in the blank) Hopefully this will speed up the FCC's process for applications for new towers, etc.

It seems like I am rather consistently writing about the passing of a broadcaster. This time I report the passing of Bob Cleland. You might say, Bob who? For me this is a personal thing as Bob was the news director of KTNT ( Now KBSG) back in 1959 when I was doing weekend air work at the station. Bob continued to work for KTNT Radio for a number of years and later left the business. He later returned to Channel 11 where he retired in 1988. Never got to know Bob really well, but he will always be remembered by me as ''the newsman" where I got started in this biz.

The FCC's continues to issue fines. WRKQ (AM) in Tennessee was asked to contribute $9K for, among other things, failing to use its call sign and operating at night with its daytime power.

Here's an area that I'll bet many stations could find themselves on the wrong side of the FCC's enforcement team. 73.3526(e)(9) requires all written comments to a station be placed in the station's Public File. Did you know that this INCLUDES email? Yep! Betcha a lot of stations receive comments via email these days and simply delete them . . . placing them in the 'electronic trash bin'. The Commish does not require you to print them to paper and put the paper in the file, you can store them electronically (another reason for keeping the disc drive) . . . and if you do store them electronically . . . you have to have a means for 'Joe Citizen' who walks in asking to see your public file to see those electronic 'comments' as well. I see this one as a big trap. For more information, check the April issue of the WSAB newsletter or contact your company FCC advisor.

The end of 'combat operations' in Iraq has meant a lot of interesting remotes for our industry. The President giving a national speech from the deck of a carrier in the Pacific was interesting in itself. As the Abe Lincoln came back into port in Everett, CNN was coordinated by Greg Thies a 2.5 Gig channel for live video as a ship to shore mobile link.

If your station has Part 74 licensed fixed, point to point, links on 950 or above . . . the time is NOW to make sure that your receive locations are indeed in the FCC's database, ULS. Revisions of the rules have been given a stay due to the efforts of SBE, allowing broadcasters a 6 month period to get the job done . . . Further, SBE will likely no longer be the coordinator as the FCC wishes type 101 coordination used. This will likely mean that commercial coordination outfits will be doing this work and they will be relying on the FCC's database. Now here's the rub. According to research by SBE, there are just under 30% of these point-to-point systems that DO NOT have data in ULS about their receiving sites. What does this mean? It means that many of these systems could get 'clobbered' by well-meaning commercial coordinators. The SBE felt that this was a very serious problem, and the FCC agreed, granting a 6-month stay. Historically a broadcaster would simply have to work with their local SBE Coordinator to make sure a new system was 'clear' . . . or to run tests, etc. After Oct 16th a call to Greg Thies or Arne Skoog to coordinate a new STL, TSL, etc., will find them telling you, 'Sorry, I can't help you.' I sincerely hope your station/company is ready for this change!

Everyone has had to endure the, " way back when . . . I only paid $___ for that" remark. Usually from a person who is happy to overlook the fact that inflation severely alters the equation. Well here's one for ya. Back in 1953 (for you youngsters, TV was REALLY new then) you could purchase a Hoffman, 17 inch, Easy Vision TV set for $199.95. What was Easy Vision you ask? It was a mustard colored filter placed over the black and white tube that was supposed to make TV watching easier on the eyes. Ok now . . . go ahead . . . see what kind of TV set you can buy for 200 Bucks . . . using TODAYS money! Gee, what happened to halo-light?

In closing this month -- Some gems from a first grade class. In this case, the teacher gave her students the first half of an old proverb and asked them to complete it . . . the results are . . . well . . . read on -

Strike while the ...... bug is close.
Don't bite the hand that ...... looks dirty.
If at first you don't succeed ...... get new batteries.
Where there's smoke there is ...... pollution.
You can't teach an old dog ...... new math.
No news is ...... impossible.
Never underestimate the power of ...... termites.

And finally from a youngster that truly understands the value of money -

A penny saved is ...... not much.

Til next month - remember that summer never begins in this area until after the cloudburst on the 4th of July.

Clay Freinwald, K7CR, CPBE

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The End User

by Rich Petschke
Radio Technology Manager
Fisher Radio Seattle

I admit it. I was a bit more than intrigued when the stories about the "iLoo" broke last month. In case you missed it, the "iLoo" is a standard portable toilet (or "loo," as the British call it) equipped with not only high-speed Internet access, but also a wireless keyboard and a height-adjustable plasma screen located directly in front of the seated user. In May, the UK division of MSN announced plans to release the iLoo (including the possibility of including special toilet paper imprinted with URLs that users may not have tried!). After several rounds of off-again, on-again press releases. Microsoft reported they have now canceled any plans to produce the "iLoo."

My intrigue with the "iLoo" was not about why one would want to surf the 'Net while taking care of business; it was centered around what a tech support call would be like if a problem occurred while using the device. It might go something like this:

Tech support rep: "iLoo support. How can I help you?"

iLoo user: "Yes, I'm having trouble opening an attachment from my webmail account. When I click on the attachment the whole thing crashes. I can't even flush."

T: "Sir, the ILoo's Internet access doesn't affect the plumbing operations."

i: "But when I click the "Flush" button on the screen I get a 'this program has performed an illegal operation and will be shut down' message. Nothing works after that."

T: "Have you tried rebooting the iLoo?"

i: "OK. How do I do that? Where's the reset button?"

(And, after a few rounds of questions and answers, but no resolution to the problem....)

T: "Sir, I'll dispatch a technician to look at the problem. Please stay in the iLoo until the technician arrives."

i: "Oh great. Now I'll be late for my meeting."

Now there's bonafide proof that some things in life that don't need to be computerized. And there's also some places where one just doesn't need Internet access!

Last month, we talked about the continuing lack of a single standard for recordable DVD discs. Apparently, Pioneer, one of the largest DVD-R-standard supporters, has decided on providing compatibility rather than single format support. The company is releasing its DVR-A06 drive this month, which, like the Sony DRU-500 family of drives, supports all recordable-DVD formats (except the seldom-used DVD-RAM standard). Like the Sony, the DVR-A06 will also burn CD-R and CD-RW discs. And Microsoft, which, to date, has endorsed only the DVD-R+ standards, announced at last month's Windows Hardware Engineering Conference that it will build in support for all recordable DVD standards in future versions of its operating systems. It definitely looks like a single recordable-DVD format won't be decided this year-and maybe not even in '04.

Most new computers come with a bunch of USB ports. And if you ever wished you could plug in some non-computer devices (like a cup warmer, or electric toothbrush) to your USB ports...well, you're in luck. An outfit called the Dreams Come True Company ( is offering electric cup warmers, electric toothbrushes, even a knee blanket -- all powered by a computer's USB ports. I suspect these devices might be handy if you go camping with your laptop.

Finally this month, if you have a lot of airline miles and don't want to blow them all on tickets, you can now use them to bid on eBay! Last month the online auction site introduced the "Anything Points" program, enabling users to convert frequent-flier miles to account credits which can be used to pay for auction items. For now, only American and Midwest Airlines are participating in the "Anything Points" program, but eBay expects to add additional partners in the future.

That's it for June. Send your questions, comments and suggestions to Till next month...all the best!

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Marriage Communications

From: Lynn Osburn

While attending a marriage seminar on communication, David and his wife listened to the instructor declare, "It is essential that husbands and wives know the things that are important to each other."

He addressed the man, "Can you describe your wife's favorite flower?"

David leaned over, touched his wife's arm gently and whispered, "Pillsbury All-Purpose, isn't it?"

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Air Travel

Thanks to Lynn Osburn
Subject: humor: Air Travel

via BBC Network:

At Heathrow Airport today, an individual, later discovered to be a public school teacher, was arrested trying to board a flight while in possession of a compass, a protractor, and a graphical calculator. Authorities believe he is a member of the notorious Al-Gebra movement. He is being charged with carrying weapons of math instruction.

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A few more of "You Might Be An Engineer If" jokes that you may not have heard:

Michael D. Brown N7AXC CSRE
Brown Broadcast Services, Inc., Portland

  • In college, you thought Spring Break was metal fatigue-caused failure.
  • At an air show, you know how fast the skydivers are falling.
  • You have saved power cords from your broken appliances.
  • You bought your spouse a set of matching screwdrivers for her birthday.
  • You think that people yawning around you are sleep deprived.
  • You've tried to repair a $5 radio.
  • You stare at an orange juice container because it says CONCENTRATE.

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Newsletter Committee

Bill Harris

Garneth M. Harris

Newsletter archives are available online.
Visit for an index of newsletter back issues.
Note: Old newsletters may contain outdated information, web links or email addresses. News archives are not updated when relevant information changes.

Views expressed herein do not necessarily reflect the official positions of the Societies, its officers, or its members. We regret, but are not liable for, any omissions or errors. The Denver SBE and SMPTE 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 or SMPTE chapters are permitted to use excerpts if attributed to the original authors, sources, and/or the Denver SBE/SMPTE Newsletter.