HD Radio

HD Radio, using digital technology, brings with it clear, static-free, fade-free AM radio reception with near FM quality listening. HD Radio also provides FM radio reception that rivals CD audio quality (no noise, distortion or interference), and can have several subchannels for carrying content different than the main signal. For example, an HD FM radio station could carry soft rock on its main signal, while one of its subchannels carries religious oriented programming and another carries live coverage of sports events. To accomplish all this, two changes are necessary:

1. The radio station must broadcast an HD signal. This requires a fairly expensive upgrade in the station’s broadcasting equipment (costing $100,000 or more) and also requires a license from the HD patent holder, iBiquity, who also imposes advertiser usage fees for using the HD technology. All these costs are paid for by the radio station. Listening to HD Radio is free for consumers, so it’s up to each individual radio station to gauge their market and decide whether or not they want to (or can afford to) broadcast in HD. There is no governmental mandate to switch to HD, as there was with digital TV. Whether or not stations broadcasting an FM HD signal provide content for the subchannels will be an individual choice for that station. Currently, according to iBiquity, there are more than 2,000 HD radio stations and more than 1,000 subchannels in the US.

2) Since almost all stations that are HD transmit a "hybrid" signal containing the usual standard signal in addition to the new HD digital signal, your old radios will work fine but will not have the features offered by HD. However, to take advantage of the features that HD broadcast offers, you must have an HD radio receiver. HD radios are priced from $50 and up available in a variety of types: small earphone only portable radios, tabletop units, clock radios, HD built into upper end home A/V receivers, built into iPod docks and more. New cars now offer HD radios as well.

We tested a small FM portable HD radio from Insignia (www.insigniaproducts.com, $50), and the local FM HD radio stations did sound clearer and crisper than standard FM stations. The radio’s scan function found 25 local FM stations, of which nine broadcast in HD and eight carried subchannel programming. The radio sports 10 presets and is simple to use.

AM HD broadcasts present a problem not found on FM HD: adjacent station interference. For a variety of technical reasons, non-HD AM stations whose frequency is adjacent to an HD AM station can suffer annoying hissing or "rain-like" noise from the adjacent HD station. This problem is currently the subject of a lawsuit involving the FCC and hopefully will be resolved.

In the meantime, FM HD radio can extend listening enjoyment with its extra features for the rest of us.