Monday, September 24, 2007

HD Radio: Skepticism is Spreading

Could the cracks in the HD Radio picture be starting to show? Is there a change underway in the mindset of radio industry execs that HD Radio - as it is being positioned - is not the answer to radio's future?

Sunday, September 23, 2007

Review: Radiosophy HD100 — HD Sounds, But At What Cost?

Remember those crappy $15 AM/FM/cassette radios from the 80s? The HD100 looks just like one and has the sound to match. Basically a glorified clock radio, it has a chintzy, careless interface with speakers that spew a tinny unrefined sound. And while carefully tuning the HD stations results in an audible improvement over analog alternatives, the overall quality is still poor — even for a $100 device. Frankly we’d be happier keeping our money and sitting in silence.

Editorial on the recent approval of HD Radio (IBOC) in the USA

On Thursday the 22nd of March, 2007 the Federal Communications Commission approved all facets of digital broadcasting in the USA. In particular, AM stations will soon be authorized to begin 24/7 use of their first adjacent frequencies for digital sidebands.

What this does is open the door to significant interference to all AM stations. A 50kw clear channel station can run a digital transmitter at far more power than would be authorized for any conventional station in that location on those two adjacent frequencies. It will be interesting from a rather perverse sense to see what happens at night..

I have had two HD Radios, and found that the digital signals are very fragile, and cover about half the radius (1/4 the area) of a good analog signal. Electrical noise from many sources like car ignition, light dimmers and bad wiring can easily disrupt things.


HD Radio is a new technology that enables AM and FM radio stations to broadcast their programs digitally, a tremendous technological leap from today's familiar analog broadcasts. These digital broadcasts provide listeners with radically improved audio quality and reception and new data services. Signal fading, static, hisses and pops are a thing of the past. Data services such as displayed song and artist information, weather and traffic alerts and much more will revolutionize the way you experience AM and FM radio. And it's all FREE for consumers, just like today's analog AM and FM radio.

AM Stations May Be Affected by USA HD Radio--CAB

As of September 14, US AM radio broadcasters that have implemented HD Radio will be allowed to transmit their digital signals at night as well as in the daytime.

Canadian AM stations operating on frequencies that are first and second-adjacent to powerful US stations may experience increased levels of skywave interference after dark as a result of this recent FCC decision.

AM Hybrid IBOC Parameters

The following technical parameters and spectrum details were gleaned from the IBOC system specifications, which are now (as of April 16, 2005) a part of the NRSC-5 IBOC Digital Radio Broadcasting standard.

IBOC Interference Calculations

The procedure outlined here is intended to estimate the impact on the nighttime groundwave coverage of a Canadian AM station from a U.S. AM IBOC station located on a 1st adjacent channel. Although it is not the only situation that may cause interference, 1st adjacent IBOC is the dominant source of nighttime problems, due to the strength of nighttime skywave and the fact that most of the digital power resides in the 1st adjacent channels. Nearly all of the power that gets dumped into the adjacent channels is in the primary digital sidebands, which are located between 10 and 15 kHz from the carrier frequency of the IBOC station.

Digital radio in Canada

The Canadian Radio-Television and Telecommunications Commission has revised its policy on digital radio.

Saturday, September 22, 2007

Tune into HD Radio

The broadcasting industry has been abuzz about HD Radio for the past couple of years. It's an all-digital radio-broadcasting standard that--unlike the paid-subscription model of XM and Sirius satellite radio--is available for free. Plenty of HD Radio stations are now on the air (more than 600 at last count), but many are simply digital simulcasts of the existing AM or FM stations you already receive--great for improved, static-free reception but not much else.

HD on QVC -- Lipstick on a (Roast) Pig

As the saying goes, you can't put lipstick on a pig, but somehow, iBiquity has managed to get QVC to sell HD radios to its vast home shopping network audience.

HD Digital Radio™ Momentum Accelerates with Debut on QVC

The HD Digital Radio Alliance, a joint initiative of leading broadcasters to accelerate the rollout of HD Digital Radio, announced today that three popular HD Radio receiver models will premiere on QVC, Wednesday, September 26 at 10 PM (ET).

[Comment 10-5-2007 - it's been reported that about 500 radios were sold on QVC in the first 20 minutes of this show]

AM HD Radio 24 x7 as of September 14, 2007

In March of this year the Federal Communications Commission authorized AM HD radio stations to begin twenty-four-hour per day broadcasting on September 14, 2007. This is a major shift in the FCC Rules that formerly protected broadcasters against the expected and now prevalent nighttime interference to stations on channels adjoining an HD broadcaster.

Statement of Jeff Littlejohn

Jeff Littlejohn, VP/Engineering for Clear Channel, the world's biggest radio broadcasting organization, reports to the National Radio Standards Committee that use of HD-AM at night will be "profoundly deleterious" to established AM listenership.


The radio industry has been afflicted with a dubious new technology that threatens to end forever your ability to listen to distant nighttime stations on AM, or use the multitude of existing analog AM radios in your car, office and home to enjoy AM programs. It's called "HD-AM"

Night of the Bees

Radio listeners across America are trying to hide from a monster, but there is no shelter. After spending its adolescence in technical trials during daytime hours, IBOC has now come out at night.


The purpose of this blog is to bring together information related to the use of in-band, on-channel technologies in the medium wave (AM) broadcast band, aka HD Radio (tm)