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RF Goes To NAB

In the early 1990s, UHF broadcasters were introduced to a new television transmitter amplifier technology that brought with it efficiency well above any previous technology. The inductive output tube (IOT) allowed broadcasters to achieve much higher plant efficiency, which translates directly to lower power bills.

When the NAB opens its doors this month, attendees will see some familiar looking transmitters, as well as a few very new ones. But this time around, it'll pay to look at whose tubes are in which transmitters.

For example, Axcera's flagship transmitter, the Visionary, won't look too much different, but if you peer inside, you'll see a new, very high efficiency tube installed. The company is excited about it. But whose tube? That answer is so secret that at press time all the company would say was that it had a non-disclosure agreement with the supplier until it shows up in the exhibit, along with its low-power packages and standard lineup.

Thales Broadcast & Multimedia will be showing a new transmitter, but once again, no word on what's in the final amplifier. Wherever you look in the transmitter exhibits, be sure to check out whose tube is installed.

Chief among the innovators who've led the higher efficiency revolution are CPI, Litton (now part of the Northrup Grumman Electron Devices Group), Marconi/EEV, and Thales Tubes & Components. And whether you check out these new tubes in the transmitter or tube exhibits, you'll hear the good news about how you can dramatically cut your station's biggest overhead expense: the power bill. The numbers may surprise you.

More Savings Available

Undoubtedly, the interest in low- to medium-power transmitter packages will be running high at NAB, because you can expect to hear quotes from $150,000 to $300,000 as opposed to $750,000 and up for high power.

As an example of what you can get in a package, Thales Broadcast & Multimedia offers its new solid state Affinity transmitter. LDMOS amplifiers are available in power levels of 50, 100, 200, 500, and 1,000 W. Affinity uses the ADAPT exciter common with BeachHead (a basic solid state upgradeable package) and the DXC Millennium IOT transmitter.

Affinity is the company's most basic package. It can also be offered with an optional "starter pack" that includes the SD encoder, an Amber remultiplexer, and a static PSIP generator as "a complete solution in a box."

In fact, all transmitter manufacturersÑeven Dielectric with its lease packageÑare now offering starter packages, and they aren't all dead-end investments, because most of them are upgradeable in the field to full power. What you get in that package however, depends on what you think you need, so the ballpark prices could fluctuate considerably.

One option to look at is the new antennas coming out of Andrew. The company can supply you with an antenna that's very light-weight yet durable, has little windloading, and is very economical. In other words, you could probably put its new antenna on almost any tower without needing tower structural changes.

What About Solid State?

All transmitter manufacturers will warrant a closer look, especially when your preference is solid state. Actually, all of the transmission low- to medium-power packages start with solid state. Depending on the model you select, the build-out to high power later on can include IOTs, or be totally solid state.

Last year LARCAN displayed a transmitter concept called the DTV-ready Magnum. This year the Magnum is up and running. It's a scaleable rig that will be available in 2.5-, 5-, 10-, and 20- kW models. It features LARCAN's new 2XW PA circuitry (with twice the output power density) with new LDMOS technology. The system includes broadband stripline combiners, a maintenance-free technology, and redundant amplifiers and power supplies. Magnum's hot-pluggable broadband amps can be used on any UHF channel, and no tuning is needed. And like all LARCAN transmitters, it has full diagnostics, simplified monitoring that can quickly locate out-of-tolerance conditions, and can be remotely controlled.

Of course, any station still without a DTV transmitter should pencil in a visit to Acrodyne (with a powerful lineup that includes Rohde & Schwarz transmitters and upgradeable packages). Known for introducing IOT technology to the industry, its core engineering team is applauding the company's increasing sales to stations outside the Sinclair Broadcast Group. Broadcasters should also check out EMCEE Broadcast Products. Best known for low- and medium-power transmitters, the company will show off its nifty full-power ABS line.

Harris will offer something for everyone interested in RF, including its newly-designed economy Ranger package, along with unique monitoring and control systems and the popular high-tech solid state and tube transmitters. Since it has always been keen on utilizing high efficiency devices, you'll want to check on whose tubes are in those rigs.

Itelco can't show its full lineup of solid state and IOT transmitters because its catalog looks like a New York City phonebook. If you are unable to locate its distinctive booth right away, check out the South Hall map in the NAB guide.

K Tech checks in with an ideal transition low power line, along with Armstrong, Bext, NEC, and Superior Broadcast products. Don't Forget Microwave

Interesting innovations are now available from RF Technology (now owned by Microwave Radio Communications or MRC) and a host of other RF manufacturers that will be covered in detail in the June issue of DigitalTV. That report will also include N Systems and its system. The company was so secretive about it at press time that no pictures were available. Nucomm is another "must see" microwave booth visit, as it unveils its answers for COFDM remotes.

MRC will take the wraps off STRATA and REPORTER. STRATA offers integrated COFDM/MPEG for ENG applications. It's compact and portable, with the latest integrated DVB-T COFDM and MPEG-2 technology. It internally supports formats that include analog FM, COFDM, QPSK, 16 QAM, and 64 QAM, or any external 70-MHz modulator signal from an outside source. The REPORTER, a new mini-transmitter, is one of the first commercially available digital radios with inboard COFDM and MPEG technology that can fit on the back of a camera or worn on the operator's belt clip. It frees up the reporter from dragging cables on ENG shoots. See you at the show!