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Industry News

Is Diversity in U.S. Radio Engineering Possible?

Radio World
4 years 9 months ago

In this issue we continue our coverage of racial diversity in U.S. radio tech, focused for now on the experiences of Black engineers. We started last issue with a story featuring the experiences of three African American radio engineers. Here we sought out several broadcast companies and organizations to invite their perspectives and what, if anything, should be done about the situation.

It’s uncontentious to assert that there is a lack of Black engineers in technical positions across the U.S. radio broadcast landscape.

Radio is not unique in this regard. Its lack of diversity mirrors that of many technology-based industries. But a quick peek into any engineering session room at a major trade show makes clear how dramatic the disparity is.

“I’ve only worked with a few Black engineers through my entire career,” one corporate-level engineering professional told Radio World. It’s a common observation for many in the field.

A diverse workforce is the backbone of successful organizations in various industries, according to many business experts. So how can U.S. radio — often criticized for a lack of diversity in ownership and upper management, especially in commercial radio — better reflect the world around it by diversifying technical hiring?

Social activism during the COVID-19 pandemic has raised the issue of systemic racial inequities throughout society, and many companies in and out of radio are making public gestures toward doing better.

But for technical people, this comes at a time when the overall numbers of broadcast engineers and engineering jobs appear to be shrinking thanks to industry consolidation and retirements.

And data is scarce. The Society of Broadcast Engineers and the National Association of Broadcasters do not collect demographic information on membership. Nor do they collect data like the number of broadcast engineering jobs held by African Americans.

“SBE recruitment efforts are aimed at all within the broadcast engineering and media community, regardless of color, race or gender,” according to a statement from SBE.

But Mike Cooney, chief technology officer for Beasley Media Group, told us the broadcast industry is well positioned to attract a more diverse workforce.

“Given the incredible technological advances that continue to evolve on a daily basis within our industry, there are more opportunities than ever before. I think having engineering and technology-based training facilities and organizations dedicated to promoting diversity in the workplace are great ways to attract diverse candidates,” Cooney said.

Beasley Media Group, which has 64 radio stations in 15 markets, is committed to a diverse workplace and encourages anyone with a passion for pursuing a career in broadcast engineering to do so, Cooney said.

Recent attention to race and social justice should only spur more creative ways for the industry to achieve a more diverse workplace, he said.

Radio World reached out to several other leading radio groups. Queries to iHeartMedia and Entercom for comment were not answered. Cumulus Media “respectfully declined” to comment.

“Basic benchmarks”

The problem may not be a lack of candidates but a broken “pipeline.”

David Honig, president emeritus and senior advisor at the Multicultural Media, Telecom and Internet Council, said that issue has existed for a long time.

“For decades there have been pipeline issues impacting African-Americans in all STEM [science, technology, engineering and mathematics] career paths. African-Americans face entry barriers at every stage. High school course assignments, college counseling and lack of mentors,” Honig said, “plus out-and-out employment discrimination, both conscious and unconscious.”

Honig said a good starting point would be the development of partnerships and relationships, including internship and for-credit externships, for minority candidates.

Ernesto Aguilar, program director of the National Federation of Community Broadcasters, said radio broadcasters need to “look at themselves” when searching for solutions to improve diversity within their organizations.

“There are the obvious things, such as outdated recruitment efforts, problematic workplace culture and frankly not really trying that hard. But then there are more subtle issues. Quite a few organizations hire engineers purely as contractors with no benefits.

“In addition, contractors may not receive the investment that regular staffers do, so there can be power disparities, out-of-pocket expenses for training and issues that make these roles less desirable,” Aguilar said.

There are things Black job candidates can do, Aguilar said, that can benefit their job search and to find employment within engineering ranks.

“I’d encourage any prospective candidate of color to ask to see the diversity, equity and inclusion goals of anywhere they’re interviewing; to request a copy of the organization’s staff audit to see its hiring trends the last five years; and to talk with staffers of color.

“With that in mind, this is an opportunity for those broadcasters who are serious about diversity to have some of the basic benchmarks above,” Aguilar said.

The NFCB, which serves community radio stations within the public media system, in July released a guidebook to its members on issues of diversity. The Diversity Equity and Inclusion in Community Radio guide offers community radio stations “a simple, actionable framework to implementing training, setting up a DEI committee, doing programming audits, managing resistance to change at your station, and potential initiatives you can work on.”

Aguilar said it remains to be seen whether recent racial justice protests foster a greater practical commitment from broadcast managers and executives, mostly White, to hire and retain executives, leaders and staff across gender, race and generation.

Moving the needle

NAB Chief Diversity Officer Michelle Duke says one key obstacle facing Black applicants hoping to enter broadcast engineering is a lack of experience.

“When we have had students of color graduate from our Technology Apprenticeship Program, one issue we have faced with hiring is that many stations aren’t able to hire entry-level engineers,” Duke said, noting that it’s not a problem unique to minority candidates.

The NAB Leadership Foundation’s Technology Apprenticeship Program, a six-month program that includes a diversity component, provides hand-on training and prepares a person to take the Society of Broadcast Engineers Certified Broadcast Technologist Exam.

Addressing the lack of Black broadcast engineers begins with education, which won’t happen overnight, Duke said.

“It has to be a cohesive industry-wide effort to partner with organizations and schools that train student engineers. Building ties with organizations like the National Society of Black Engineers would give our industry more exposure to Black engineering students who are looking for their first job opportunity,” Duke said.

The next step, Duke said, is for the industry to find ways to keep potential Black engineers engaged.

“Either through hiring them or creating contract positions that these students can strive toward acquiring. We are doing our best to lay the groundwork, and we need radio stations and companies to work with us to get the best results,” she said.

“This takes time, but if the radio industry is sincerely interested in moving the needle, it can happen.”

Comment on this or any story. Email mailto:radioworld@futurenet.comwith “Letter to the Editor” in the subject field.

The post Is Diversity in U.S. Radio Engineering Possible? appeared first on Radio World.

Randy J. Stine

EBU Cites Benefits of Public Radio Music

Radio World
4 years 9 months ago
The Netherlands Radio Philharmonic Orchestra, with Karina Canellakis, chief conductor, at left.

The author of this commentary is head of radio for the European Broadcasting Union, an alliance of public service media with 115 member organizations in 56 countries. Read about its mission here.

Each day, audiences across Europe access the music programming on public media through the EBU Members. In doing so, they can open a window on a vast variety of musical genres, accounting for around half the programming hours broadcast.

In the very beginning of radio, broadcasters needed to invest in live music-making, because commercial music interests were concerned that radio airplay would affect their sales. So studio ensembles, radio dance bands and radio choirs were born.

Of course, we have come a long way from those days, but the extraordinary investment in musicians and music continues. Even during this troubled year for the music sector, public media organizations have been seeking opportunities to bring live music back to their services.

Obligation and privilege

With an abundant amount of commercial music available elsewhere, for instance through streaming services, what can public media add to an already rich mix?

Because of the special way in which EBU Members are funded, there is the obligation and indeed the privilege of supporting national musical life. This can involve giving platforms to unsigned bands, providing experience and visibility to young composers and musicians, and commissioning new music.

Yes, in short, public media is there to take risks and to stimulate creativity on a national basis. Case studies have shown that the range of music played is wider than on commercial channels.

Public radio then provides opportunities for musicians and an enriched listener experience. And of course, within the EBU, it is massively important that these cultural events, produced nationally, can be shared on an international basis.

Through the extraordinary Music Exchange within the EBU, in a typical year around 5,000 hours of content is exchanged. This is not a typical year; but in the coming months we look forward to steadily rebuilding as more live events happen. Thankfully we are already seeing the green shoots.

Economic boon

In common with other broadcasters, EBU Members track audience trends and platform usage; but what has never been fully analyzed is the extraordinary economic impact of the investment which leads to the positive listener experiences recalled above.

We are therefore pleased to have commissioned work involving Oxford Economics and the EBU Media Intelligence Service, work that clearly demonstrates that, in addition to cultural and societal benefits, the investment yields a substantial economic benefit (see “The Economic Impact of Public Radio’s Music Activities,” Oxford Economics, 2020, free access with new user log-in).

Across the EBU Members, we can count more than 120 music ensembles, around half of them orchestras, the remainder choirs and smaller ensembles. This directly creates over 17,000 jobs, including 5,800 musicians directly employed, at the cost of more than 1 billion euros. Across the European Union, this accounts for around 20% of the overall investment in the music and radio sectors.

If we then factor in further impacts from the necessary procurement to support the activity, as well as staff spending, we can see a broader impact of more than 3 billion euros, supporting over 50,000 jobs.

Additionally, and not quantified in the report, there is a notable effect from public media encouragement of listeners to explore new genres, discover emerging musicians, namely in the purchase or streaming of a wide range of music genres.

The highly positive contribution here is around the support this gives to launch new careers and — in the process — contribute to building national cultural capital, in many cases resulting in exports through touring and international sales.

When we appreciate the choice of music on our radios, when we hear one of the many orchestras and choirs perform, we should certainly enjoy that special moment.

However, there is a wider picture, namely the substantial economic benefits of this activity, sustaining the artists involved and giving them a regular platform, but also nourishing the economies of the countries where such investment takes place.

An EBU webinar on Sept. 22 will explore “PSM Supporting Music: The Economic Impact.”

The organization also has released a List of Radio Ensembles run by EBU Members, including 56 orchestras, 47 choirs and 24 additional ensembles.

 

The post EBU Cites Benefits of Public Radio Music appeared first on Radio World.

Graham Dixon

Pai Calls for Transparency on Foreign Government Sponsored Broadcast Content

Radio World
4 years 9 months ago

A proposal to establish new disclosure requirements for broadcast TV and radio content sponsored or provided by foreign governments has been made by FCC Chairman Ajit Pai.

Pai’s proposal comes in the form of a Notice of Proposed Rulemaking, which would amend section 73.1212 of the FCC’s rules to require a specific disclosure at the time of a broadcast if a foreign governmental entity provided the content.

[Read: FCC Releases Guidance on Requests for Fee Flexibility]

The current rules, according to the commission’s announcement, do not specify how and when foreign government sponsorship of content should be disclosed to the public. The proposed rules would provide standardized disclosure language for stations to use in such instances to specifically identify the foreign government involved.

“American TV viewers and radio listeners have the right to know if a foreign government is behind the programming they are consuming,” said Pai. “With some station content coming from the likes of China and Russia, it is time to update our rules and shed more sunlight on these practices. I hope my colleagues will act quickly to approve this proposal so we can help the American public be informed when they may be watching or listening to foreign-government propaganda.”

The existing rules date back to the Radio Act of 1927 and were designed to prohibit stations from disguising advertising as program content, the FCC says. Pai believes that these new rules would expand transparency by applying it to foreign government and political parties.

 

The post Pai Calls for Transparency on Foreign Government Sponsored Broadcast Content appeared first on Radio World.

Michael Balderston

World College Radio Day Approaches

Radio World
4 years 9 months ago

Though much of college radio station activity has been hamstrung by COVID-19 limitations, early October will see the return of World College Radio Day.

Officially Oct. 2, the 10th annual World College Radio Day will feature rocker Bret Michaels as its Official 2020 Ambassador. Michaels is best known for his work with the band, Poison.

He said, “In this difficult time, there has never been a more important year, or a better year, for the hope that college radio brings. … Music itself is the soundtrack to life and helps drive us through these unprecedented times. When dorms and campuses may be quiet, this should be the time for college radio to be going strong.”

Michaels himself will work with his foundation, Life Rocks Foundation, to donate $10,000 to select college radio stations.

The post World College Radio Day Approaches appeared first on Radio World.

RW Staff

iHeartRadio Will Support Hybrid Radio in North America

Radio World
4 years 9 months ago

Hybrid radio is about to take a much bigger place on the American radio stage.

Audi of America announced it is collaborating with iHeartRadio to bring the capability to drivers in North America.

iHeartRadio is rolling out hybrid radio compatibility via more than 600 stations in the United States and Canada.

Hybrid radio allows users to keep listening to favorite stations even when out of range of the signal. It also enables metadata-driven graphics and other capabilities.

Audi is introducing hybrid radio on certain 2021 vehicles, which begin to go on sale in the U.S. this month. The company has been an early advocate for this technology approach.

The details

“Equipped on select 2021 Audi vehicles with the new MIB 3 infotainment suite, Hybrid Radio seamlessly allows listeners with an Audi connect Prime or Plus subscription to switch between broadcast and digital radio signals when they have entered or exited radio signal territories for uninterrupted listening,” Audi announced.

“When the vehicle is cycled off and on again, it is able to retain the radio station, picking up the digital radio channel via internet connection. Collaborating with iHeartRadio brings the experience to life.”

An image from an Audi receiver shows available stations. A small box labeled “Web” indicates reception via the WiFi channel instead of OTA.

As Radio World has been reporting, platforms that combine OTA and internet connectivity are starting to take a bigger role in the competitive landscape.

The open standards organization RadioDNS has been active in raising awareness and encouraging adoption of hybrid platforms.

[Related: “Hybrid Radio Picks Up Momentum,” June 2020 overview article}

Getting support from the largest radio company in the country is an obvious big step forward for the hybrid format in the United States.

The announcement was made by Pom Malhotra, director, Connected Services, Audi of America, and Michele Laven, president of Strategic Partnerships Group for iHeartMedia.

Laven was quoted saying, “The innovative functionality Audi is introducing via their Hybrid Radio experience allows yet another way for that companionship to be seamlessly extended beyond the range of the broadcast signal keeping the consumer connected to their favorite station, no matter where the road takes them.”

In the case of these Audi customers, the hybrid platform uses an integrated 4G LTE Wi-Fi hotspot to maintain a radio station when out of range of the signal.

[Related: “RadioDNS Aims to Establish Metadata Consistency”]

 

The post iHeartRadio Will Support Hybrid Radio in North America appeared first on Radio World.

Paul McLane

GM Extends Deal With SiriusXM

Radio World
4 years 9 months ago

Thanks to a new contract extension, SiriusXM says “nearly all” new General Motors vehicles soon will be available with the satellite service.

The new agreement runs through 2027. “GM will increase vehicles equipped with SiriusXM to nearly all Chevrolet, Buick, GMC and Cadillac vehicles beginning with model year 2021,” it stated.

[Read: SiriusXM Adds Volkswagen to the 360L Family]

Chevy, Buick, GMC and Cadillac customers purchasing or leasing new or preowned SiriusXM equipped vehicles will continue to get a three-month trial subscription to SiriusXM All Access.

General Motors also will continue to expand its deployment of the SiriusXM 360L hybrid radio platform, which is more personalized and provides on-demand content capabilities.

The announcement was made by Steve Cook, EVP, Sales and Automotive, for SiriusXM, and Santiago Chamorro, VP for Global Connected Services at GM. SiriusXM also noted that GM was the first to begin factory-installing SiriusXM, in 2002.

 

The post GM Extends Deal With SiriusXM appeared first on Radio World.

Paul McLane

NAB Will Honor Russell M. Perry

Radio World
4 years 9 months ago

Russell M. Perry will receive the NAB National Radio Award during the 2020 Radio Show.

He is described by the National Association of Broadcasters as “a trailblazing media entrepreneur, a champion of journalism and a celebrated humanitarian in his community,” according to NAB President/CEO Gordon Smith in the announcement.

The association noted that Perry began his radio career in 1993 with the founding of Perry Publishing & Broadcasting Co. and the purchase of an AM station in Oklahoma City, Okla.

[Read: Radio Show Announces Virtual Lineup]

“Since then, he has grown the company into the largest independently owned African-American broadcasting company in the nation, with 22 radio stations across the southeast United States.”

Earlier he was co-publisher of The Black Dispatch, and in 1979, became the owner and publisher of The Black Chronicle, a paid weekly newspaper serving Oklahoma.

Perry has also held high posts in Oklahoma state government as the secretary of commerce and secretary of economic development and special affairs. He’s active in efforts to promote and restore African-American-owned commerce in Oklahoma City.

Past honors include induction into the Oklahoma Association of Broadcasters Hall of Fame, the Oklahoma Journalism Hall of Fame and American Urban Radio Network Broadcasters Hall of Fame.

The Radio Show will be held virtually this year over a full week in early October; it is produced by the NAB and the Radio Advertising Bureau. Info is at the Radio Show website.

 

The post NAB Will Honor Russell M. Perry appeared first on Radio World.

Paul McLane

FCC Introduces Plan to Increase Staff Diversity

Radio World
4 years 9 months ago

Increasing staff diversity is a priority for leaders of the Federal Communications Commission. That resolution led to the creation of the Early Career Staff Diversity Initiative, a joint effort by FCC Chairman Ajit Pai and FCC Commissioner Geoffrey Starks to advance equitable opportunities for underrepresented undergraduate, graduate and law school students.

During the commission’s monthly meetings, FCC commissioners regularly welcome a cadre of college-age students as interns to the FCC, where an internship offers valuable real-world experience, industry connections and often leads to employment in the communications sector. For the last several years, however, the commission has only offered voluntary, unpaid internships. According to the commission, otherwise-qualified students may not have the opportunity to pursue these opportunities, including students from underrepresented communities.

[Read: NAB Foundation Launches Diversity Resource]

Since the communications sector impacts every American’s ability to access affordable and reliable communications, the FCC said, its employees should reflect the nation’s diversity. As a result the Early Career Staff Diversity Initiative laid out the following new components:

  • Starting in January, 2021, the FCC will provide a select number of paid internships to law, graduate or undergraduate students each semester and summer. These internships should create opportunities for students who may otherwise be financially unable to participate in unpaid internships at the FCC.
  • The FCC will invest additional resources to recruit students from historically black colleges and universities, Hispanic-serving institutions, tribal colleges and universities, and other minority-serving institutions to increase the diversity of the applicant pool for the commission’s internship, Attorney Honors and Honors Engineering programs.
  • The FCC said it will increase recruitment efforts with affinity groups such as chapters of the National Black Law Students Association and the Society of Hispanic Professional Engineers to increase awareness about available internship and career opportunities.

In all, these efforts seek to diversify the talent among commission staff at the earliest stages of their careers and ultimately increase diversity in the communications sector overall, the chairman and commissioner said in a statement. With this initiative, the FCC joins other public and private institutions that have committed resources to create a more diverse workforce.

“Throughout my time at the commission, I have been committed to advocating for equity in the policies we implement,” said Commissioner Starks, who brought the idea for a new diversity initiative at the FCC to Chairman Pai. “And in the wake of the larger movement for racial justice, it is especially important for the commission to do its part to advance policies that center our most marginalized and create opportunities internally for our agency to ensure we have more diverse voices at the table.”

Chairman Pai said that promoting diversity in the tech and telecom sectors has been an important priority for him as FCC chairman.

“Establishing a paid internship program will help students who would otherwise have to forego an internship due to financial constraints,” he said. “And targeted outreach will ensure that more students from diverse backgrounds can participate, which benefits the FCC and the communications sector as a whole.”

The move was applauded by the Multicultural Media, Telecom and Internet Council (MMTC), which said the group was pleased to support the FCC in this bipartisan effort to address diversity challenges in the media, tech and telecom sectors.

“Since 1969, the FCC has expected its licensees to undertake similar steps to expand their employment pipeline to include minorities and women,” said MMTC Chair and Treasurer Ronald Johnson. “Our hope is that this leadership by Chairman Pai and Commissioner Starks will encourage those the FCC regulates — and others in the industry — to do their part to achieve a diverse pipeline in terms of talent, ownership and in the supply chain.”

Additional details, including how to apply, will be made available this fall.

 

The post FCC Introduces Plan to Increase Staff Diversity appeared first on Radio World.

Susan Ashworth

My Vacuum Tube Headphone Amp Project

Radio World
4 years 9 months ago
Rummage material, (Click here to enlarge.)

Like most of us during what advertisers like to call “this difficult time,” I was compelled to spend a fair amount of it “working” from home.

Truth be told, I hadn’t worked so hard in years. My wife kept me so busy with household projects that I was begging to go back to work just to get some rest!

But there were the inevitable frequent bouts of boredom. I often found myself at my workbench, staring at the various boxes and bins of parts, wondering what I could do with them.

Fortunately, my wife had given me a copy of “Designing High-Fidelity Tube Preamps” last Christmas. (Yep, she’s a keeper!) The book is by Merlin Blencowe, known on the internet as The Valve Wizard (www.valvewizard.co.uk). It’s a rather ponderous tome for a guy like me who barely passed Algebra; but it’s loaded with lots of great design ideas.

One chapter toward the back discusses a transformerless headphone amplifier built around a White cathode follower tube stage.

As I rummaged through my parts stash, I came across some spare tubes and decided to issue myself a challenge: Could I build a working vacuum tube headphone amp with only the parts I had on hand?

Breaking the Rules

With Blencowe’s text as a starting point, I then stumbled across a similar design by Pete Millett (www.pmillett.com). His design was a bit more complex and included some high-end output transformers. It had been reworked by another fellow DIYer, Ian Thompson-Bell (www.customtubeconsoles.com), for use in his tube console.

Schematic 1, (Click here to enlarge.)

Ian has been very helpful to me with past tube projects, so I had a good look at that.

Eventually, I came up with a schematic, shown small in Schematic 1. You can obtain the schematics for this story by emailing radioworld@futurenet.com, with “Curt’s schematics, please” in the subject line.

When you look at the schematic you’ll see that it breaks a few design rules. Remember, it’s based on what I had, not what I wanted!

Normally, no one in their right mind would build such a thing using 12AX7s, which are normally used as high-gain preamps (especially guitar amps). Obviously, the high impedance of the output would have a hard time driving a typical pair of headphones.

Picture 1, (Click here to enlarge.)

Still, I soldiered on, slapping it together with a power supply I managed to assemble. See Picture 1.

I was amazed it actually passed audio, but not surprisingly, the output was anemic at best.

I went ahead and added an input stage based around two halves of another 12AX7, one for each channel. (I have no idea how I acquired so many spare 12AX7s. If I didn’t know better, I’d swear they were breeding!) See Schematic 2.

Schematic 2, (Click here to enlarge.)

The input stage is a very common design, seen in numerous mic and instrument preamp stages. The plate resistors could stand to be larger, but I happened to have a pair of large 56 kohm resistors. What I didn’t have was a stereo pot for the volume control, so I had to substitute two regular 10 kohm pots and adjust each channel separately. The coupling capacitors on the inputs are an oddball value, because, again, they’re what I had. Other designers vary the value of the cathode resistors on the output stages anywhere from 160 ohms to 470 ohms. I had a few 330 ohm resistors on hand, so we land somewhere in the middle. I found a couple solder lug strips to make the point-to-point wiring a little neater. See Picture 2.

This version passed much more signal, owing to its nearly 60 dB of gain. That’s clearly overkill for a headphone amp, but it was able to drive a pair of AKG K240 headphones. This was likely due to sheer brute force, as the impedance mismatch would make any proper designer’s hair stand on end!

Picture 2, (Click here to enlarge.)

A colleague suggested much larger electrolytic capacitors for output coupling to handle that a little better. The closest thing I had was a pair of huge 470 µF/200 V power supply caps. The 12AX7s on the output certainly gave it some “crunch” at higher volumes. If you’re going for a “tube” sound, I suppose it would work.

The power supply was put together using some parts I had stripped from an old tube project I was no longer using. The supply design is lifted directly from that project.

Schematic 3, (Click here to enlarge.)

It’s fairly simple as tube supplies go. I suppose I could have gotten away without the TL783 regulator for the plate supply, but it was handy. In fact, it was already bolted to a heat sink with a 78S12 regulator that I could use for a nice, clean, DC filament supply. I mounted the other components to a piece of perf board. I didn’t have a 100 ohm 2 W resistor, though; so I had to connect a 47 ohm and a 56 ohm in series. Close enough for rock and roll.

See Schematic 3.

Ideally, the output tubes would be 12BH7s, which are common in this setting.

Wouldn’t you know it? I came across a box of old radio tubes, and buried under the pile were two 12BH7s! Amazingly, they both still worked! They also happen to have the same exact pinout as a 12AX7, so no rewiring was necessary.

Granted, they were mismatched, which led to one channel being slightly louder than the other. I also found out the hard way that those tubes get HOT when working. I’m told this is normal.

Picture 3, (Click here to enlarge.)

So now I had a working device, but it was a terrifying looking pile of parts on the workbench.

I set about constructing a proper enclosure for it. I had recently built an equipment rack for my studio using a sheet of cabinet-grade birch plywood. I used some scraps to assemble a small box. Digging through a storage bin, I found a few square metal plates someone had given me years ago. Hated to just toss them … (I swear, I’m not a hoarder!) One of these plates would be perfect for a top panel for the jacks, tube sockets, and such. See Picture 3.

A little punching and drilling, a coat of Testor’s model paint, and some lettering, and the panel was done. Some stain and a coat or two of polyurethane, and the box was completed. See Picture 4.

I managed to fit everything inside, which was a surprise, considering I simply based the size of the box on the dimensions of the metal plate (about 7 1/2 inches square), and how much scrap wood I had.

Picture 4, (Click here to enlarge.)

I decided to mount the tubes on the outside, mainly for the coolness factor; but also for the other coolness factor, as in keeping the 12BH7s cool. This definitely gives it an antique vibe.

The finishing touch was a Bakelite knob from a stash of old radio knobs an even older friend gave me years ago. See Picture 6.

So, it works, if only barely.

What improvements can be made to the design without breaking the bank and reinventing the wheel in the process?

Picture 5, (Click here to enlarge.)

For starters, I will likely order a matched pair of 12BH7s. Some of the output transformers I researched gave me sticker shock, but Ian Thompson-Bell suggested a pair of Edcor XSM Series transformers. They are very reasonably priced, just under $20 each, and could be bolted to the top of the enclosure, behind the tubes. They would eliminate the giant coupling caps, which would then be replaced with much smaller 1 µF polyesters.

I’d also replace one power transformer with a toroidal type, to match the other one. Then, in the interest of neatness, I might go to the trouble of designing a PCB for the rest of the circuit. See Schematic 4.

Schematic 4, (Click here to enlarge.)

But, for something thrown together with what was on hand, it was a fun and interesting project and a great conversation piece.

Curt Yengst, CSRE, is engineer for Lighthouse TV in Allentown, Pa., and a longtime RW contributor.

Email us with your own DIY ideas at radioworld@futurenet.com.

 

The post My Vacuum Tube Headphone Amp Project appeared first on Radio World.

Curt Yengst

Radio World Announces Fall Best of Show Recipients

Radio World
4 years 9 months ago

Radio World has announced the recipients of the 2020 Best of Show Award Virtual Edition program.

The recipients are:

RCS Revma

Telos Alliance Omnia Enterprise 9s High-Density Virtual Audio Processing Software

Wheatstone Blade-4 for WheatNet-IP Audio Network

“We give a special tip of the hat to all of our entrants this year,” said Radio World Editor in Chief Paul McLane. “These companies have been working hard to keep advancing the state of our industry’s technology despite the very real physical and economic challenges caused by the pandemic.”

All winners and nominees will be featured in a Program Guide distributed to readers of four Future publications involved in the program: Radio World, PSN, TVBEurope and TV Technology.

Manufacturers nominate products for a fee. Winners are chosen by each brand’s editorial staff or technical contributors. Not all entries win.

This award program is normally conducted at this time of year in conjunction with the annual IBC show (it is separate from the Best of Show Awards given during the annual NAB Show).

It is intended to honor outstanding products and help raise awareness for the new products and services, this year honoring products launched or featured around a virtual IBC Showcase.

The post Radio World Announces Fall Best of Show Recipients appeared first on Radio World.

Paul McLane

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