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The Commission adopts a Report and Order eliminating the common antenna siting rules for FM and TV broadcaster applicants and licensees

Eagle Broadcasting, LLC enters into Consent Decree to Resolve Political File Investigation

Alan Hughes

The author comments here after reading the commentary “What Can ATSC 3.0 Teach Radio” by Dan Slentz.

Over-the-air TV, like broadcast radio, is the cheapest and fastest way to communicate to large audiences. These are one-way communication systems where the whole audience gets the same thing simultaneously.

It is possible to separate parts of the audience using the Alternate Frequency System available in DRM and DAB+ digital radio, which can specify areas as small as 7 x 7 kilometers (4.35 miles x 4.35 miles). It requires GPS to be automatic from the user’s perspective, but it won’t work indoors since the needed satellite GPS reception is blocked.

Since broadcasting and OTA are one-way systems, how and where are the data to make appropriate individualized advertising to be gathered? Smart TV’s microphones and cameras? Existing smart speakers provide data, which could be sold, which will enable control like cable TV companies have had.

Is the broadcast industry ready for the privacy issues of having microphones and cameras always on while watching TV?

Dan Slentz in “What Can ATSC 3.0 Teach Radio?” suggests using the MAC address. Consider the data requirements to send for an audience of a million TVs and sending the different content data as well as the 48-bit MAC address a million times. How long would that take? The remaining available data rate available in HD Radio once the sound data has been used is tiny for additional content such as unique addressing and its unique information.

After 20 years, ATSC 3.0 is finally an admission that COFDM modulation, which is used in all other digital TV systems outside of North America and South Korea, is much better than ATSC 1.0. COFDM can reject reflected signals (in the analog days these were called ghosts). The extensive use of outdoor TV antennas has kept broadcast TV popular as it is free to the user and the signal reliably is good.

ATSC 1.0 uses MPEG2 compression, the least efficient system; and in much of the rest of the world MPEG4 compression is used, which halves the data rate, allowing for more HD programming. Now ATSC3.0 is capable of Ultra High Definition because of the latest compression, which halves the data rate again. However, UHD requires more data for the extra sharp images.

I agree that having more channels from the same transmitter does not necessarily improve profits. In Australia all TV stations transmit two high-definition programs and three standard-definition programs. The SD programs are generally old reruns, cheap programming or advertorials that the advertisers pay the broadcaster to transmit. These programs generally get much lower ratings.

The problem with FM zoning is that the translators are located in areas where the main signal is poor, not where a particular audience type lives. DRM and DAB+ use the Alternate Frequency System which can specify the four-corner GPS co-ordinates of a rectangle as small as 7 x 7 kilometers and send the data to that area. It is not part of the HD Radio specification.

Advertising the presence of the steakhouse down the road is already being done by Google via cellphones and smart speakers.

The reason the cable companies became dominant in TV was because of the selection of “Never Twice the Same Color” (i.e., NTSC analog TV) and later ATSC 1.0, which with the use of indoor antennas shows the wrong hues, ghosts and, in ATSC, unreliable reception.

ATSC 3.0 can broadcast up to 57,000 kbps. It is difficult to have new innovations with HD Radio because the highest bitrate is only 96 kbps, and nearly all of this is required to get reasonable sound quality or for additional, poor sound-quality, subchannels. For AM HD Radio the number is either 20 or 40 kbps.

In HD Radio, you need to use the primary and secondary signals. In all-digital HD FM, the secondary digital signal is radiated at 1% of the main signal power, which makes the reliable digital coverage area much smaller than analog. By comparison DRM can have up to 186 kbps and all digital signals are of the same power which is not limited by interference to and from adjacent channel broadcasters including your own.

The author is a broadcast technical author from Australia and has spent a lifetime in training technicians. Radio World welcomes opinion and points of view on important radio broadcast industry issues. 

[Also by this author:“A Better Way to Revitalize U.S. Radio”]

 

The post More Thoughts on What ATSC 3.0 Can Teach Radio appeared first on Radio World.

“Best of Show” Up Close is a series of Q&As with participants in Radio World’s annual springtime Best of Show Awards program.

Winmedia nominated its winSales system. We asked Jesus Vazquez Miguel, international sales manager, for more information.

Radio World: What is winSales and what is its targeted application?

Jesus Vazquez Miguel: WinSales facilitates advertising management for radio, TV and advertising agencies.

Jesus Vazquez Miguel

Fully integrated with the winMedia playout system, WinSales can also easily be interfaced with most playout systems currently in the market. Therefore it is a major asset for sales and financial teams as well as a very powerful monitor tool for management, to follow the evolution of the turnover or the invoicing cycle of the different projects.

WinSales is intuitive. It makes it possible to respond in real time to market issues. It includes a calendar of events to anticipate and create special offers. The sales manager can organize suitable and targeted advertising offers.

RW: What sets it apart from similar offerings in its product class?

Vazquez Miguel: WinSales is the only product in its range that is able to send the content scheduled within the platform directly into the dedicated slots of the playout system.

In other words, when an advertising campaign is booked in winSales, in one click, it can be sent into the playlist of the automation system.

Lastly, winSales bridges the gap between the sales and production. The customer can provide the media corresponding to his campaign. In that case, the audio or video file will automatically be inserted in the playlist. If the media is not provided at this stage of the booking, the playout will generate a production sheet in which the audio will have to be added.

RW: What are the benefits of a “secured extranet”?

Vazquez Miguel: The WinSales offers a secured connection to the main server, an end-to-end encrypted connection, but also cloud data backup on multiple servers.

RW: In light of the pandemic, what kind of remote capabilities does it offer?

Vazquez Miguel: In these unprecedented times, we really have to work on improving the ability of our customers to go through their whole day-to-day workflows without being able to access their workspaces.

When we designed winSales years ago, we already had in mind that people’s ways of working were changing, and this is even more important when it comes to the various roles within the advertising space.

WinSales is a web-based platform; therefore, it can be used remotely from any type of device, from a computer, to a tablet or a smartphone in its responsive version, while offering the exact same capabilities as what a salesperson will get from being at his office.

For instance, he would have an extensive access to his sales catalog — advertising spots, sponsorship, events, packages, promotions, digital and social networks — and would be able to give availabilities and rates to his client in real time

RW: What does it cost?

Vazquez Miguel: The system starts from $300 (U.S.) per month.

RW: What else should we know about winSales or winMedia’s business these days?

Vazquez Miguel: In the era of uberization, winSales is fundamentaly the intermediary between the broadcasters and the advertisers, and provides a range of solutions in order to remove the stress and the admin on their daily basic workflows.

More than a website, winSales is a true market place where advertisers can simply upload the different products that are part of their catalog throughout the year, and where broadcasters can compose their campaigns as simply as by putting the different type of products they need in their baskets.

WinMedia is more than ever improving its products by transforming them to respond to the major need the world is facing at the moment: being able to work efficiently and deliver from anywhere. As a result, we offering more web-based and user-friendly interfaces, easy-to-set-up packages and a full offer of remote presentations.

[Read about all the nominees and winners in the award program guide.]

The post “Best of Show” Up Close: WinMedia WinSales appeared first on Radio World.

Founded as a teachers’ college in the 1860s, Truman State University has evolved into “Missouri’s only public liberal arts and sciences institution.” And radio and media play a role in that mission.

Radio World contacted David C. Price, Ph.D., to learn more about the vibe around the station right now, part of our ongoing coverage of issues facing college and educational media.

Price is associate professor of communication and advisor to KTRM(FM), KKTR(FM) and  TMN(TV).

Radio World: Describe the media programs and operations there.

David Price: The Department of Communication at Truman State University sponsors five media outlets, along with the digital/social media associated with these outlets: a campus newspaper, “The Index”; an online magazine, “Detours”; a television studio, TMN-TV; an NPR-affiliate station, KKTR 89.7 FM, which re-airs programming from KBIA out of the University of Missouri in Columbia; and a student-run radio station, KTRM 88.7 FM.

RW: Tell us more about that.

Price: KTRM is a student-run eclectic station. Students who want on-air experience are given one-hour shifts and are allowed to select their own formats.

We have approximately 75 to 100 students participating, with the vast majority doing on-air programs. In between shifts and when classes are not in session, the station airs Adult CHR on the Simian automation platform from BSI.

The station describes itself as playing “genre spanning alternative and underrepresented music,” emphasizing independently produced music and music from smaller record labels.

KTRM is a Class A non-commercial station running 3,500 watts. KKTR is also a Class A non-commercial station running 3,500 watts.

KTRM has one air studio with a three-microphone set up for interviews, a back-up studio production room and two editing suites equipped with Adobe Audition and Adobe Premiere Pro.

The station is entirely student run, with a support staff of faculty advisors and an engineer; a secretary is available for purchasing and bookkeeping. Only the engineer, Norm White, works full-time supporting the radio and television outlets. The faculty advisor is given one quarter released teaching load and handles the required FCC documentation. (There are two faculty advisors at this time, one for radio and television, the other for newspaper and magazine.)

The mission of the station is educational — though we have to remind students of that frequently. There is some integration with the curriculum, but it is indirect so as to maintain the editorial and management independence of the media outlets.

[Read about the history of Truman State University.]

RW: Other media facilities on campus?

Price: The campus public relations office has a videographer and photographer on staff and are actively producing print, social media and video productions. We do share some equipment with them when needed.

The sports information area in the athletics department has video and audio production staff and equipment, though the live game productions are done by a contracted professional radio station.

The campus library has an audio/video production room for students who wish to self-produce content.

RW: How has the pandemic affected operations of the radio station? 

Price: Our students were on spring break when we were told operations were to cease. The radio station has been playing Simian nonstop since then.

The faculty advisor kept the station running (since students were not allowed on campus) by adding an externally produced weekly public affairs program and monitoring the equipment.

When students return to campus, they will once again be responsible for the public affairs programming. Under the student station manager, some content has been created, emailed to the faculty advisor who then uploaded it to the log by the faculty advisor. Students have also updated the playlist, which was emailed to the faculty advisor, who then uploaded the new songs and added them to the log. The student station manager decided to feature only Black artists in June to support the Black Lives Matter messaging.

The student station manager and an assistant were permitted to enter the studio to create the new playlist and upload related content. That was the only time students were in the station from March 6 to the end of July.

[Related: “High School Station Stays on the Air, Minus Its Students”]

Students were allowed back into the studio beginning Aug. 3; the station manager and one staffer came in on Monday to being preparations for fall semester.

As of now, the student body is expected to return to campus Aug. 12, and the station is expecting to have student broadcasters on-air at that time to resume control of daily operations, including all the public affairs programming, content creation, uploading, modifying logs, and other management tasks.

During the last two months we have been actively discussing how to maintain a safe workspace when we have 75 to 100 students coming in and out the studio and changing personnel every hour. The student station manager has been involved in these discussions.

We struggle with developing cleaning protocols, especially with microphones and audio boards. We have requested, but not yet received, Plexiglas dividers to separate student work areas and alcohol-based cleaning supplies. We purchased microphone covers, though we are uncertain how effective they will be.

RW: For the educational year ahead, what are the priorities of the station or your broader programs?

Price: Our top priority has to be protecting the health of the students. We will repeatedly tell students that the concept of “the show must go on” is no longer true. We have the Simian backup so if a student doesn’t feel safe or doesn’t feel healthy they are not punished in any way for not being there for a show. This is true of all of our media outlets.

We are planning for students to return to the studio as in the past. However, our student station manager is encouraging and welcoming off-site productions, where students can pre-record segments or shows at home and submit them for loading into Simian. We hope this option decreases the number of bodies going in and out of the studio, but still keeps students involved.

RW: You mentioned the Simian system. Describe the rest of the air chain.

Price: The air studio has an Audioarts D75 digital audio console with Electro-Voice RE20 mics; a DaySequerra M2 HD Radio Modulation Monitor; Sage Digital Endec; Symetrix AirTools 6100 Broadcast Audio Delay; and Rane HC6S Headphone Console.

We also have three Denon DN-C635 Compact Disc/MP3 Players; a Technics SL-1200MK2 turntable; a JK Audio Broadcast Host Digital Hybrid; Samson Servo 200 Amplifier; Symetrix 581 Distribution Amplifier; and Dell Optiplex 7020 computer with two monitors. We expect students to supply their own headphones for health/sanitary reasons.

The backup/production studio has an Audioarts R55e On-Air Console with Electro-Voice RE20 mics and Dell Optiplex 7020 computer with two monitors. For field productions we’re using a Comrex Access IP codec.

The transmitter is on campus here in Kirksville, about a half-mile SSE from the studio. The STL microwave link is a Moseley SL9003Q. The RF chain at the transmitter site includes a Harris HD transmitter with an Orban audio processor; and the antenna is an ERI LPX-4E.

RW: How would you characterize the feelings of students these days about careers in radio and in media more broadly?

Price: Our campus is located in a relatively rural part of the state, and I see more interest in time-shifting audio (podcasting) than in live broadcast. We don’t have a commuting audience, for the most part, so dayparts are less significant.

In my teaching, I pitch the value of local content that print can’t and doesn’t do as well — particularly sports and weather broadcasting. We regularly broadcast Truman athletics (even though there is a professional station also broadcasting the games).

Our radio students are also big into community engagement, sponsoring live music performances on campus or in community venues, which draw large audiences.

RW: Anything else we should know?

Price: Although the pandemic has disrupted operations, the bigger threat to student media is the continuous budget cutting coming from legislators and the governor of the state. As they cut funds for higher education, the cuts are passed down to our operations also.

We fear that if a major piece of equipment were to fail we would not be able to find the money to replace it. Some of our technology is aging, and our engineer has done his best to keep it going, but there are weak links in the production chains that could be big-budget problems.

The post Student-Run KTRM Serves Truman State appeared first on Radio World.

Above, the D.J. Everett III Radio Room. See the end of this article for more photos of the room.

Many successful career people are grateful for mentoring they received on the way to the top. But few have honored a memory as passionately as has Beth Mann.

Ham Broadcasting is all about local. It owns five stations and markets itself as “western Kentucky’s leader in marketing and promoting all types of businesses.” It tells advertisers on its website, “We use a unique and powerful combination of radio and new media platforms to grow all types and sizes of businesses and organizations. We are 100% locally owned, 100% locally operated, 100% locally oriented and 100% locally committed to help you grow your business.”

The late D.J. Everett III

Mann, its owner and general manager, wanted to commemorate the contributions of her predecessor D.J. Everett III. She did so by creating a Radio Room named for him at the WKDZ/WHVO studios in Cadiz, Ky. It opened to the public last October during the station’s 10th annual Pink Out fundraiser for breast cancer research.

Everett worked as a broadcast journalist and TV general manager, as well as a radio owner. He was inducted into the University of Kentucky’s Journalism Hall of Fame in 2012. He died in 2015 at the age of 67. “Under his leadership, WKDZ was recognized numerous times as one of the best radio stations in the U.S. in its market size,” according to the Times Leader newspaper in Princeton, Ky.. “Everett was also known for his civic engagement and community involvement.”

This Radio Room is a gallery and meeting space also dedicated to the physical history of radio in Cadiz locally and in the United States.

Among its highlights are an extensive, beautifully staged collection of antique radio receivers behind glass walls; the Legends Room, a replica 1966 radio production studio; and a public meeting space in the center of the facility.

The D.J. Everett III Radio Room covers 1,850 square feet, entered through a pair of custom-made doors adorned with door handles styled after the RCA 77-DX microphone.

Beth Mann, WKDZ

“I started working with D.J. Everett when I was 17 years old, first in television and then in radio here at Ham Broadcasting,” said Mann. “D.J. was a father and mentor to me, and when he passed away in 2015, he left me a number of vintage radios. I took over the company at that time — it had been part of his long-term plan for me to do so — and I wanted to find a way to honor his memory and showcase his collection. The D.J. Everett III Radio Room grew out of that.”

An Inspired Radio Collection

The radios in the room cover from the earliest days of the medium up to the 1960s. Included in the displays are a 1919 Commerce Radiophone crystal set: a 1923 Atwater Kent “breadboard set,” so-called because the components are laid out on a flat piece of polished wood with no protective case; and a wonderful selection of 1930s-era “tombstone” and floor console radios from the Golden Age.

“We also have a 1943 metal-cased Echophone radio, which was used by the troops during World War II,” said Mann. “My favorite is the gorgeous dark green 1946 Bendix Caitlin, which came in a plastic case that would melt if the radio’s tubes got too hot.”

Annette Hargis contributed a diary in which her great-grandmother noted the day WKDZ went on the air. “We have a special place set aside in the D.J. Everett III Radio Room for this masterpiece,” Mann posted.

Also on display are photos, posters and other historical memorabilia. “We even have a diary donated by Annette Hargis, in which her great-grandmother Mrs. Wiley Stallons noted WKDZ’s first broadcast on April 8, 1966,” Mann said.

The Legends Room radio studio features 1966-era radio equipment that would be familiar to many broadcasting veterans, including a suspended RCA 77-DX microphone, a Gates Producer dial-type control panel, a cart tape machine for commercials and idents, a rotary dial telephone and a Revox reel-to-reel machine of a kind this author used in his own early radio days.

“The Legends Room is decorated with photos of our staff back in 1966, plus photos that trace D.J. Everett’s distinguished broadcast career,” said Mann.

Add the many tables and chairs available for community meetings, and one can see why the D.J. Everett III Radio Room has caught the imagination of Cadiz residents and radio fans in general.

“The overall reception to our project has been phenomenal,” said Beth Mann. “It is a chance for us to celebrate D.J.’s legacy, and also to show the world that local, community-centric radio is alive and well, and a career worth pursuing by young people.”

See below for photos of the radio room. For more about this impressive installation head to www.wkdzradio.com.

Annette Hargis contributed a diary in which her great-grandmother noted the day WKDZ went on the air. “We have a special place set aside in the D.J. Everett III Radio Room for this masterpiece,” Mann posted.

 

The entrance to the Radio Room with its microphone-styled door handles.

 

A display about radio during World War II includes ads from radio manufacturers explaining their work for the government making military radio equipment.

 

 

Early radio displays

 

A replica of a 1960s studio setup.

 

The post A Visit to the D.J. Everett III Radio Room  appeared first on Radio World.

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La Zeta 95.7 Inc. enters into Consent Decree to Resolve Political File Investigation

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A Quu promotional image

Radio data technology company Quu announced a deal to provide Salem Media Group with “ad sync” services on 28 FM stations in 17 markets.

Quu offers services to let radio stations manage RDS/HD in-car stereo displays with an eye toward revenue and a better listener experience. Beasley Media Group is among its investors.

It says its technology lets stations generate revenue by enhancing over-the-air spots with client logos and text to be seen by consumers on their desktops, mobile and dashboard devices.

The announcement was made by Quu CEO Steve Newberry and Salem Media Group President of Broadcast Media Dave Santrella.

[Related: “NAB EVP Newberry Plans Exit”]

“Salem Media Group further underscores the broadcaster’s commitment to providing unique advertiser experiences and optimum service offerings by featuring album art, showcasing station information and creating a complete 360-degree visual and audio-based advertiser experience for clients and listeners,” Quu said in a press release.

Santrella was quoted saying that radio serves and engages but that “radio needs to improve the user experience so that we look as good as we sound.”

[Related, 2019 story: “NextRadio Outcome Leaves a Void”]

The post Quu to Provide Ad Sync to Salem appeared first on Radio World.

Michael O’Rielly’s renomination as an FCC commissioner was rescinded by Pres. Donald Trump Monday, according to published reports.

O’Rielly was originally nominated to the FCC by President Barack Obama and was sworn in November 2013. He was sworn into a second term in 2015. His term expired in June.

O’Rielly is a conservative who generally favors deregulation, including of ISPs and lifting media ownership rules given the rise of competition from cable and broadband and satellite, and was instrumental in loosening KidVid regs on TV stations.

[Read: O’Rielly Seeks to Knock Down Barriers]

The renomination of O’Rielly for another term was reportedly put on hold in July by Sen. Jim Inhofe because of the FCC’s decision to allow Ligado Networks to deploy a lower-power national mobile broadband network.

NAB President and CEO Gordon Smith released the following statement in response to the news O’Rielly’s nomination had been rescinded:

“Mike O’Rielly has been a sterling public servant for as long as I have had the privilege of knowing him, a span of time covering my years in the Senate and throughout my time leading NAB. He is the consummate professional — smart, diligent, honest, and fair. For these and many other reasons, NAB has been proud to support his continued service at the commission. But for these reasons also, I have every confidence that he will succeed wherever he casts his lot.”

There has been no comment from the FCC or O’Rielly at the time of publication.

 

The post Trump Rescinds O’Rielly Nomination at FCC appeared first on Radio World.

RJ Russell

The SBE’s engineer of the year is probably someone better known to television engineers than radio, but he plays a crucial role in U.S. frequency coordination, and has been helping to revitalize that volunteer program.

RJ Russell will receive the Engineer of the Year Award from the Society of Broadcast Engineers in its upcoming virtual national meeting. The award is named for Robert W. Flanders.

The society also named two recipients of the SBE Educator of the Year award: Fred Baumgartner and Roland Robinson. That award, which is named for James C. Wulliman, recognizes outstanding service and excellence in sharing knowledge through teaching other broadcast engineers.

[Read: “SBE Takes Its National Meeting Online”]

RJ Russell has been an SBE member for 21 years and has served in several board and committee positions.

After service in the Marine Corps he worked for a number of TV groups, and he was a broadcast engineering manager on the Sprint Nextel Project for four years, assisting TV stations with the 2 GHz repack and reimbursement. He also designed and built a new broadcast center for Brigham Young University and he has been active on the ATSC 3 project station in Cleveland.

“Most recently, RJ accepted the critically important position of SBE frequency coordination manager as an independent contractor through his company, TBSI,” SBE stated in its announcement.

“RJ has a vast and unique knowledge of the frequency coordination process and is the SBE’s major representative to the Department of Defense and its contractors in the SBE-DOD-NAB transition process at 2 GHz,” it said.

Fred Baumgartner

“Through the direct involvement of RJ, who is respected very highly by the DOD, FCC and NTIA, the SBE and its members, broadcast licensees, and the DOD have benefited from the careful, meticulous planning that RJ has worked exceptionally hard on to maximize DOD-coordinated use of 2 GHz without constraint on broadcasters.”

He is overseeing preparation of a national database of 2 GHz users to help the work of SBE frequency coordinators. “He has revitalized the program at a difficult time in the history of volunteer frequency coordination,” SBE said.

Last year’s recipient was Charlie Wooten.

The 2020 educators of the year are both longtime SBE members.

Fred Baumgartner has worked for 17 years with the Ennes Educational Foundation Trust, leading Ennes Workshops during the NAB Show and producing the SBE presentation on NextGen TV during the 2019 PBS TechCon.

Roland Robinson

Roland Robinson is an instructor of classes in broadcasting and video production at Bates Technical College in Tacoma, Wash., and has implemented an SBE-approved certification curriculum in broadcast classes.

“The curriculum was recently renewed unanimously by the SBE National Certification Committee, the members being impressed by the curriculum presented by Robinson,” SBE stated. He is also active in Washington state emergency alerting.

MultiCAM Systems won the SBE Technology Award for its Air Bridge video offering.

SBE Chapter 37 in Washington, D.C., won the Best Educational Event for the NextGEN TV Summit in January, held in conjunction with SMPTE.

The full award list including chapter membership and attendance awards awards is here.

The post RJ Russell Is SBE’s Engineer of the Year appeared first on Radio World.

The history of audio processors for U.S. radio stations can be roughly divided into two chapters. The first, when these devices were a compliance tool for FCC regulations regarding transmitter modulation. Their job was to maintain average modulation levels between the required 85 and 100%, and ensure audio peaks never exceeded 100%. The second chapter, after the loudness wars began, when audio processors were used to create a signature sound for a station, and ensure modulation levels were kept as high as legally possible.

The Gates Sta Level AGC and SA-39B peak limiter belong to the earlier era.

Both were introduced in the 1950s, and enjoyed long service lives. They were designed around conventional textbook circuits with no “black boxes” or deep secrets about how they operated. Both were easy to set up and maintain. They were marketed by Gates throughout the 1960s and early ’70s as the perfect pair for maximum modulation.

Simple setup

The SA-39B was introduced by Gates in 1957, and replaced the similar SA-38, which was designed in 1948. It was marketed as a solution for AM, FM and TV operations.

The SA-39B’s audio circuit consisted of three push-pull stages: 1612, input; 6SJ7, intermediate; and 6V6, output. The regulated power supply had a 5V4 rectifier, and 6X5, 6SJ7 and 6L6  in the regulator circuit. A 6H6 functioned as the control rectifier. This regulated supply powered the first two audio stages. To ensure low noise, the filaments of the 1612s were run off a separate DC supply.

The theory of operation is simple. The audio output signal is sampled, rectified by the 6H6, and the resulting negative voltage connected to the second control grids of the 1612 input stage. As the output voltage increases, the grid becomes more negative, lowering the gain of the amplifier. Through compression levels up to 20 dB, distortion remained at a respectable .05% or less.

Compared to today’s audio processors, there were few adjustments and options to consider when setting up the SA-39B. Attack time was fixed at .001 seconds. Release time was adjustable via a six-position switch on the rear panel. Position 1 had a recovery time of .2 seconds, and each successive position added an additional .2 seconds. Position 3, with .6 seconds was the recommended starting point, and could be adjusted faster or slower to suit the format.

A tweak inside the limiter was used to set the front panel meter for 0 dB compression with no input. Then, it was simply a matter of increasing audio input until normal programming showed about 5 dB of compression. This setting allowed sufficient headroom for the occasional intense peak energy.

Output levels could be adjusted to +20 dB. If that was too much, two fixed attenuator pads could easily be inserted into the circuit.

[Read more tech history: “Proof of Performance, 1970s Style”]

A nice feature of the SA-39B was the six 1/4” phone jacks on the bottom of the rear panel which were wired to measure cathode current of the audio stage tubes. With a 1/4” phone-to-banana   plug patch cable, it was a simple matter to check these currents with a VTVM. Normal currents for each stage were indicated on the schematic.

Phone jacks made balancing the push-pull stages of the SA-39B easy. An octal-based electrolytic made replacement of the power supply capacitors a simple plug and play procedure.

There were two reasons for regular checks. Cathode current is a good indicator of tube life and when it begins to fall, the end is near. Second, push-pull circuits only work well when the tubes are balanced, and tubes don’t always age at the same rate. Imbalance can lead to increased hum and distortion, and in the case of the 1612s, thumping during low frequency passages.

Maintenance was fairly simple, with the usual tube checks and logging socket voltages. Access via the drop-down front panel gave access to most of the resistors and capacitors, neatly laid out on two circuit boards. Earlier tech manuals for the SA-39B documented component designations, values and voltages, but that went away when the abbreviated 4-page manual was released.

Most components of the SA-39B were mounted on two circuit boards. Earlier manuals included diagrams of the component values, designations and tube socket resistances.

A nice feature of the SA-39B was the 20-20uf 450 volt power supply electrolytic, which was provided on an octal socket. These capacitors were more expensive than the conventional twist-lock style, but made replacement a plug-and-play procedure, rather than a tedious and time-consuming chore.

The Gates SA-39B, and comparable peak limiters such as the RCA BA-6C and Collins 26U-1 were among the first casualties of the loudness wars. When the FCC passed regulations allowing AM stations to increase their positive peak modulation from 100 to 125%, their days were numbered. Asymmetrical modulation called for entirely different circuits for peak limiting. By the mid 1970s, the loudness wars had spread to the FM front. When the Orban Optimod 8000 was introduced around 1976, it revolutionized FM audio processing, and conventional peak limiters began to disappear there as well.

Cult status

While the SA-39B has largely faded from memory, the Gates Sta Level has been elevated to cult status as the decades have passed. In fact, software-based audio processors often have a ‘Sta Level’ setting to emulate its unique sound.

The Gates Sta Level was the last AGC amplifier that the company manufactured utilizing vacuum tubes.

Introduced in 1956, the Sta Level was in the Gates product line for the next two decades. It had a well-deserved reputation for its unobtrusive control of audio levels. The secret was the GE 6386, a remote-cutoff twin triode. It had a long life, and never seemed to lose its wonderful linearity. A little-known fact is that the Sta Level was not the first audio processor to use the 6386.

Shortly after General Electric introduced the 6386 tube, its broadcast products division introduced the 4BA9B1 Uni-Level to take advantage of it. The Uni-Level was a stripped-down AGC amp built for a low price-point. Input and output levels were controlled by fixed resistive pads, there was no compression level meter, and minimum parts count. The tube lineup was a 5Y3 rectifier, 6386 push-pull input/control, 6AL5 control rectifier, and (2) 6V6 push-pull output. They started selling like hot cakes.

Gates wanted a piece of the action, but they didn’t want to run afoul of GE’s application patent on the Uni-Level circuit. The challenge for Gates engineers was to design a device that utilized the 6386, but was sufficiently different to dodge a patent infringement. They did this by putting an OB2 regulator for the 6386 plate supply as well as adding a 12AT7 between the 6386 variable-mu stage and the 6V6 output stage. It was totally superfluous, and all the extra gain was swamped out by negative feedback. But it did keep the lawyers happy.

A control to adjust cathode voltage of the 6V6 output stage was the only tweak to tune up the Sta Level.

One of the underground mods for the Sta level was to remove that 12AT7 and couple the plates  directly to the 6V6 grids with .5 uf mylar capacitors. The result, less noise distortion and heat, better sound. But many engineers didn’t stop there.

Back when stations used to build their own equipment, the Sta Level’s schematic was the jumping off point for far more elaborate devices. Precision resistors, high-quality audio transformers, audio attenuators and other high-end components were often used.

While the Sta Level used an OB2 to regulate power to the 6386, many home-brew designs regulated everything, often using a 6AS7 with a 6SJ7 DC amplifier and OB2 VR tube as a reference.

Some stations went all out with the metering circuit, adding a rotary or pushbutton switch to select dB compression, audio output VU, cathode current of the audio stages, DC filament voltage for the 6386 and balance of the two push-pull stages. A few circuits also included indicator bulbs for expansion, compression and when the gain was frozen. They were not terribly useful, but fun to watch.

[Read more fun radio history from Tom Vernon: “The Time Has Come to Talk of Many Things”]

TV stations often had problems with the quiet passages in films, when the AGC would suck up all the background noise up to program level. The solution was to modify the Sta Level circuit with a pot to control the DC bias on the cathode of the 6386. That would establish a platform which would limit the range overs which expansion would occur.

Setup and maintenance of the Sta Level was straightforward. Once it was connected to the console output and being fed normal program level, adjust the input level control till the meter indicates around 15 dB of compression. Adjust the output control to properly feed the following device. At many stations, this was the phone line connecting the studio to transmitter, where the peak limiter was presumably located. Finally, set the recovery time for single or double.

As shipped, the Sta Level’s recovery time for 2/3 level was 7 seconds, and 90% level in about 28 seconds. By changing the values of R36 and 37, that could be increased to as fast as 2 ¼ seconds for 2/3 level and 10 seconds for 90% level. This was a common mod for Top 40 stations. Want to slow it down instead? Then 11-1/4 seconds for 2/3 level and 45 seconds for 90% might be more to your liking if you had an easy listening format.

By changing the values of two resistors, the recovery time of the Sta Level could be increased or decreased.

Sta Level had a tweak for balancing the cathodes of the 6V6 output stage. The manual called for matching the voltages, but a more precise method was to adjust for minimum distortion at 1 kHz. That was about it for adjustments.

Due to its simple design, reliability and great sound, the Sta Level was used lots of places besides the air chain. If you purchased a Gates automation system in the 1960s or ’70s, it often had a pair of Sta Levels on the audio output to even out the levels between different sources. Stations used them in production room for the same reason. Some were wired into a patch panel so they could be deployed for sports remotes, which had notoriously erratic levels. Talk stations were known to use them on phone lines.

While both units enjoyed a long service life, advancing technology eventually caught up with them. In 1975, Gates/Harris introduced the Solid Statesman line of audio processors. This included the  M-6543 AM limiting amplifier, M-6631 FM  limiting amplifier and M-6629 automatic gain control amplifier.

The Sta Level and SA-39 pictured with this article were found while cleaning out transmitter buildings during the contract engineering days of the 1980s. The SA-39 dates from the late 1950s, while the Sta Level was manufactured in 1967. They were cleaned up and returned to good operating condition. Both are now enjoying their retirement as objects of affection in my own personal home museum of oddities.

 

 

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