Industry News

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.

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.

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.”

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.

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.

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.

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.

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.

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.

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.

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!

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.

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.

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.

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?

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.

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.

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.

Todd Schlekeway is the president and CEO of NATE: The Communications Infrastructure Contractors Association. Jim Goldwater serves as the NATE director of legislative and regulatory affairs.

NATE: The Communications Infrastructure Contractors Association has collaborated with key industry association colleagues for many years on a wide range of issues that have significantly advanced the nation’s critical communications capabilities. This month these telecom organizations partnered again to advocate Congressional action to help address the substantial workforce shortage in the industry that jeopardizes the national communications goals of expanding broadband and closing the digital divide while enhancing public safety, advancing next generation technologies and maintaining the hundreds of thousands of communications towers already in place.

NATE is a nonprofit trade organization whose membership encompasses all layers of the communications infrastructure ecosystem, and now includes over 1,000 member companies that construct, service and maintain hundreds of thousands of communications towers (broadcast and wireless), distributed antenna systems, small cell networks and broadband throughout all 50 states and 13 other countries.

[Read: Prepping a New Master Antenna for Charm City]

NATE, joined by the National Association of Broadcasters, the Competitive Carriers Association, CTIA, the Government Wireless Technology and Communications Association, the National Wireless Safety Alliance, the Rural Wireless Association and the Wireless Infrastructure Association, wrote to key Congressional committee leaders in support of legislation that would help the industry attract, recruit and train tower workers.

Our coalition cautioned that efforts to advance major telecommunications legislation during the 116th Congress, which expires at the end of this calendar year, had not yet addressed the workforce shortage. Without a commitment to ensure that there will be an adequate supply of workers, the nation’s technology development and deployment challenges will not be addressed.

Moreover, we wrote that “The ongoing pandemic illustrates so clearly how essential our industry and our workforce are, with so many Americans forced to work, study and play remotely.” Communications infrastructure is of course critical to our capacity to conduct business, engage in telehealth and ensure that radio and television stations can continue to inform our communities, while we work toward closing the digital divide and deploying 5G wireless technology and broadcast Next-Gen television in the future. These are priorities that our letter conveyed, and we are both pleased and proud to have collaborated with our very good friends at NAB on it.

We specifically identified a few pending bills that would help address workforce development in our industry.  NATE actually assisted in the development of one of them, the “Communications Jobs Training Act,” which would provide funds for job training to enhance communications tower service. It would authorize grants to community colleges, vocational institutions and military organizations to establish or expand job training programs for communications tower service, construction and maintenance.

Our letter also cited legislation designed to develop recommendations on how to address communications workforce needs. It also highlighted the utilization and coordination of apprenticeship programs.

In January, NATE Chairman Jimmy Miller testified before the Senate Committee on Commerce, Science and Transportation at a hearing entitled, “The 5G Workforce and Obstacles to Broadband Deployment.” He stressed that “the most significant challenge with which our industry and contractor firms like mine are dealing … is the shortage of a properly trained and qualified workforce that is expected to possess the diverse skill set necessary to produce the expansion of universal broadband, public safety and ubiquitous 5G coverage across North America, while completing the broadcast repack. If we are to win the hypercompetitive global race to build and deploy 5G, which will enable our national, state and local economies to leverage technologies based on the Internet of Things, smart cities, artificial intelligence and virtual reality, we must ensure that we have enough trained workers. We simply cannot meet these national goals without doing so.”

Radio World readers may be interested in hearing more about the workforce issues as it relates to the broadcast industry, and specifically the repack transition. Although the repack was scheduled to wrap up in early July, there are still a number of stations that have not completed the transition.

The broadcast repack transition helped shine a spotlight on the fact that there are a finite number of crews in the United States capable of working on tall towers. Broadcast tower work is a different animal altogether given the complex techniques, skill-sets and equipment associated with the work, not to mention working on towers ranging 1,000–2,000 feet tall.

NATE estimates that there are only approximately 40 crews (typically consisting of 5–6 tower technicians per crew) in the country that are truly trained to perform work on broadcast towers. Of these 40 crews, only about 30 are capable of performing the most complex large broadcast and arbor stick tall tower work. The other broadcast crews are equipped to perform activities such as non-arbor stick work up to 1,000 feet, small stack and crane work or helicopter work. Many of these companies have been in the industry a long time and have an experienced, but aging workforce.

These factors served to exacerbate these issues in the broadcast industry and led to some companies having to supplement their tower technician workforce by bringing in crews from select countries in Europe for this specialized, tall-tower repack work.

NATE is committed to investing heavily in workforce development initiatives that we believe, over time, can help alleviate some of the technician labor challenges both the wireless and broadcast sectors continue to face, but there is no magic wand. It is abundantly clear, however, that addressing our communications infrastructure needs is good for our nation’s economy and competitiveness, today and tomorrow. Congress could play a role in shaping the industry’s future by passing the communications workforce development legislation that has been introduced in bi-partisan fashion.

The post Telecom and Workforce Development: Why It Matters to the Broadcast Industry appeared first on Radio World.

For many readers, cold weather will be here before we know it; and that is inevitably when we find ourselves working outside around a tower. (Troubleshooting an AM antenna tuning unit after midnight comes to mind.)

Fig. 1 shows a really neat portable propane heat lamp to keep you warm outside this winter.

Cumulus Regional Engineer Justin “J.T.” Tucker found these dual propane tank-mounted heaters at a camping supply store; they are also available online. Search “portable tank-mount propane heater.”

Single units are under $50, the dual element versions pictured are around $100.

Remember, even though they are equipped with a safety shut-off valve and tip-over switch, do not use these inside your transmitter building or any enclosed spaces.

Useful videos

We received a nice note from David Mathews, who created the “Moseley 6000 Series Frequency Change” video on YouTube that we described in July. Even if you don’t have to change frequencies on that pair of STLs, David offers a number of useful tips should you ever need to get inside the boxes.

In his note, David reports a lot of “likes,” so thank you, readers!

David tells us that he’s a “sort of” retired assistant chief engineer with North American Broadcasting in Columbus. He plans on putting together future videos on other equipment.

Okay, Workbench readers: Any specific boxes you’d like to learn more about? And for the more seasoned engineers, here’s a challenge to share your knowledge with others using YouTube. If you put something together, let me know.

Swag

Workbench contributor Marc Mann writes in to thank us for letting readers know about Inovonics and their really useful Radio Hero Swag Bag. The secret’s out; Fig. 2 shows what Marc received.

If you missed the offer, there are still a few left. To request one drop an email to sales@inovonicsbroadcast.com.

MOVs and GDTs

Steven Karty saw the suggestion we shared from Paul Sagi to change out gas discharge tubes with metal oxide varistors inside your surge protection devices.

Steven reminds us to weigh the application and the equipment before making a wholesale change; although MOVs do respond more quickly than GDTs, the much higher capacitance of MOVs limits their use, especially on audio circuits.

There’s no problem if loading up the lines being protected with lots of capacitors connected to ground doesn’t degrade the signal. But many signals will be adversely affected by the extra capacitance, so MOVs are mainly used where the capacitance isn’t a problem, like inside AC powerline surge protection devices, as Paul suggested.

Because MOVs and GDTs wear out with use, Steven suggests they be replaced periodically for continued protection. The failure mode of most MOVs is shorting and (if there’s sufficient power available) melting. Although some GDTs may short, the failure mode of most GDTs is that their firing increases, so that they aren’t providing any protection.

Thanks, Steven. All good points to consider.

Gas discharge tubes are sealed devices with a gas mixture between two electrodes. When a high voltage surge is detected, the gas ionizes, providing a short circuit to ground for the surge.

The metal oxide varistor performs a similar function. The resistance of the MOV changes with voltage, becoming a short circuit when a voltage surge is detected.

Both are shunt devices, “shunting” the high-voltage transient to ground, and hopefully protecting the circuit to which it is connected.

GDT memories

In addition to surge protectors, GDTs were used in several RCA transmitters to prevent surges from damaging components.

Tucked out of the way, this little glass tube, about the size of your finger, could sometimes short to ground, depending on the intensity of the surge. The resulting permanent short circuit certainly protected the transmitter, but also meant it would not run.

Kudos to RCA design engineers (Buc Fitch?) who mounted the GDT on a snap-in bracket so (like a fuse) it could be pulled out of the circuit and easily replaced. If you have one of these older transmitters, look for it; I’ve seen instances where some engineers would remove the shorted GDT, leaving no protection.

This only invites more damage, should another surge come along.

Put it in the dryer …

Louis Bornwasser, now retired, was an FM chief engineer in the 1960s and ’70s. Later in his career he serviced and manufactured equipment for motion picture theaters, “in the days before digital.”

Louis writes to tell us that he has cleaned power cords, mic cords and air and garden hoses for 40 years using the kitchen dishwasher, though he admits that the idea we shared recently would not have occurred to him, though circuit board cleaners that he used in the manufacturing process are similar.

Louis adds: Do it without dishes.

… Or put it in the wash 

Louis brings up a good point. Although I’ve never personally done it, I have heard stories of engineers using a car wash to clean an old transmitter before moving it to a new location or frequency.

One fellow laid the transmitter in the bed of his truck and took it through. Then, he turned the transmitter over and repeated the process. He told me he supported the transmitter on a few 4×4 blocks of wood, allowing the water to drain. He removed things like doors and relays and tubes, but it apparently worked.

Another took the transmitter to a do-it-yourself car wash. Using the hand-held spray nozzle, he could reach into all the nooks and crannies to get years of grime out.  I’m hoping that one or more of our readers who have done this can write in, and maybe include a picture or two.

My concern would be things like transformers, especially the high-voltage type!  That’s the last thing you want to compromise with water and soap! Leaving the equipment to dry in the sun for a week is probably “good engineering practice.”

John Bisset has spent over 50 years in the broadcasting industry and is still learning. He handles western U.S. radio sales for the Telos Alliance. He holds CPBE certification with the Society of Broadcast Engineers and is a past recipient of the SBE’s Educator of the Year Award. Workbench submissions are encouraged, qualify for SBE Recertification, and can be emailed to johnpbisset@gmail.com.

The post GDTs vs. MOVs: Choose Carefully appeared first on Radio World.