Category Archives: AM

FCC might reduce AM clear channel power

(Source: Tom Taylor Now)

Are the protected night signals of monster 50,000-watt AMs “an anachronism?”
And is the FCC poised to do something that will frustrate late-night DX’ers? The Commission tries again to balance the role of Class A signals like KMOX St. Louis/1120, designed to serve listeners hundreds of miles away, with the desires of local AMs. The “skywave” debate is decades-old – but particularly urgent now, given the rising noise floor from all kinds of interference. The Commission just issued a “Second further notice of proposed rulemaking,” noting the rise of “FM stations, satellite radio and other media.” The first notice drew “a voluminous and diverse set of comments,” with some pointing out that “AM skywave service is sporadic and unreliable, often subject to overwhelming environmental interference, and unlikely to consist of programming tailored to the needs of distant communities.” But then there are questions about hurricane and other weather/safety warnings. In this notice, the Commission has ideas about changes to daytime, “critical hours” operation after sunrise and before sunset, and “nighttime hours.” One observer tells this NOW Newsletter says that cutting through the thicket of details, “It’s clear that there will be a further reduction in protection to the clear channel Class A stations, particularly at night. The main questions are how much protection they will retain.”

Click here to read at Tom Taylor Now.

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All-digital AM HD: WWFD’s experiment is attracting attention

(Source: InsideRadio via Ulis K3LU)

All-Digital AM Grabs Automakers’ Interest.

The fate of AM radio in the car dashboard may pass through Frederick, MD. That’s where the latest experiment on an all-digital AM signal is taking place, on Hubbard Radio’s adult alternative “The Gamut” WWFD (820). The project, in conjunction with digital radio developer Xperi and the National Association of Broadcasters’ PILOT program, is already generating interest from carmakers in the U.S and around the world.

The Federal Communications Commission in July approved a proposal to allow WWFD to turn off its analog signal for the next year while remaining an all-digital operation. The aim is to use the real-world environment to conduct experiments designed to improve the all-digital AM service.

WWFD has 4,300-watts day (non-directional) and 430-watts night (directional) and the company proposes to operate with roughly the same output when it goes digital-only, 24-hours a day. Dave Kolesar, Hubbard’s senior engineer overseeing the project, said it’s an ideal station to use for a test case since it’s non-directional by day and directional at night.[…]

The switch has already been flipped and Xperi senior manager of broadcast technologies Mike Raide said preliminary results are encouraging. “We haven’t had any problems with OEM receivers,” he said, noting he drove 70 miles from the transmitter site and still picked up WWFD without any problem. In fact, one DX listener in the Pittsburgh area, roughly 300 miles away, said they were able to hear the station during the daytime. “That’s a testament to how robust all-digital is,” Raide said.[…]

“At a time when we’re all hearing rumors about car manufacturers cutting AM from their factory offerings, something like this could come along and show the auto manufacturers that AM still matters and AM has a digital solution as well,” Kolesar said.[…]

Click here to view the full article at InsideRadio.

In August, I received a strong lock on WWFD in neighboring West Virginia via my car’s built-in HD receiver. The next day, I made this short video of my reception on the Sangean HDR-14 (read review here) in neighboring Germantown, Maryland:

I found that WWFD covered the DC metro area quite well.

Post readers: Do you believe, as this article implies, that AM HD could revitalize the band?

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Are we entering the age of atomic radio?

(Source: arstechnica via Scott Schad)

A new antenna using single atoms could usher in the age of atomic radio

The team tested their device by recording themselves singing “Mary Had a Little Lamb”

JENNIFER OUELLETTE

In the 1950s, atomic clocks revolutionized precision time-keeping. Now we may be on the verge of so-called “atomic radio,” thanks to the development of a new type of antenna capable of receiving signals across a much wider range of frequencies (more than four octaves) that is highly resistant to electromagnetic interference.

An antenna is typically a collection of metal rods that pick up passing radio waves and convert their energy into an electrical current, which is then amplified. One might argue that the good old-fashioned radio antenna has served us well since the dawn of the 20th century, so why do we need anything to replace it?

According to David Anderson of Rydberg Technologies, those antennae are wavelength-dependent, so their size depends on whatever wavelength of signal they are trying to measure (they need to be about half the size of whatever wavelength they are designed to receive). That means you need antennae of several different sizes to measure different radio frequencies.

Anderson is a co-author of a new paper posted to the arXiv describing a novel alternative to conventional antennae, based on vapor cells filled with a gas of so-called “Rydberg atoms.” That just means the atoms are in an especially excited state, well above their ground (lowest-energy) state. This makes them especially sensitive to passing electric fields, like the alternating fields of radio waves. All you need is a means of detecting those interactions to turn them into quantum sensors.[…]

Read the full article at arstechnica.

Click here to download the research paper: An atomic receiver for AM and FM radio communication (PDF).

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Hurricane Florence’s toll on radio stations and cell services

(Source: Tom Taylor Now)

The FCC last night reported that more FMs were out (20) than AMs (three). While nearly 14% of cell sites in the affected areas were out of service – and like the AM/FM picture, virtually all the outages are in coastal North Carolina. Forecasters had predicted the brunt of the storm would fall around Wilmington and New Bern, and that’s how it played out, in slow motion. Friday morning’s NOW reported the Curtis Media radio stations in New Bern were off, as well as Sinclair’s ABC-TV affiliate, WCTI-TV. Both Channel 12 and the Curtis cluster are located very hear the Neuse River, and Sinclair was forced to originate programming from Greenville, instead. WCTI-TV’s still off, as well as sister Fox affiliate WYDO (digital channel 47/virtual channel 12). Likewise, a range of radio stations including Cumulus-owned classic hits “94.5 the Hawk” WKXS and not-for-profit EMF’s contemporary Christian “K-Love” affiliate, WBNK/92.7. One of the three silent AMs carries an ominous name for the current conditions – Cumulus-owned talk “980 the Wave” WAAV. Read last night’s FCC “Status Report” here. The agency’s main page for Hurricane Florence communications is here.

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Radio World: “Who’s Got the Biggest, Meanest AM Flamethrower?”

(Source: Radio World)

More broadcasters than you might realize are helping keep the ionosphere warm (and the power companies happy)

In the May 9 issue of Radio World, I reported on a recent power upgrade at TWR’s Bonaire AM facility that brought that station close to the half-megawatt level (440 kW), allowing the station to make the claim that it is the most powerful medium-wave (MW) operation in the Western Hemisphere. After the dust settled, I thought it might be interesting to poke around a bit in the data available to see if they have a close (or even not-so-close) contender for second place for this title.

With only a few exceptions, U.S. stations have been capped at 50 kW since this power level was authorized by the Federal Radio Commission in the late 1920s. Powel Crosley Jr.’s WLW 500,000 kW 1930s “experimental” operation is one very well-known example, as it received a lot of publicity during the five years or so during it operated before being powered down. However, there was another much less well-known superpower operation during that period (it actually beat WLW to the punch by putting 400,000 Watts on the air about three years before Crosley was ready to belt out his hundreds of kilowatts).

[…]Surprisingly, there is one U.S. AM station that has the necessary paperwork and equipment to operate at 100 kW full-time. However, it’s not listed in the FCC’s AM database. I’m referring to the VOA’s “Radio Martí” in Marathon, Fla. which operates on 1080 kHz.

The VOA station (it sports no call sign) appears to be the only operation in its class in the U.S. and Canada, but it if you cross the border into Mexico, you’ll find “muchas estaciones de radio” that emit lots more than a puny 50,000 “vatios.”[…]

Click here to read the full story at Radio World.

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