More HD radio news


An interesting take from a non-broadcaster that gets it mostly right.    The premise for HD radio™, as the author states, was to serve two purposes; improve sound quality and add extra programming channels.  I have a few issues with this statement:

Regarding the improved signal, that still holds true, and can be especially beneficial for AM radio, which has struggled for some time with signal degradation.

I would argue the opposite. HD Radio™ has done nothing to improve the signal quality of the AM band. It has, in fact, degraded the band further by adding digital hash to adjacent channels, limiting the on-channel analog bandwidth to less than 5 KHz and creating on-channel background hiss.

Thus, HD Radio™ has done neither of those two stated goals.  In addition to that, from the radio station owner/operator’s perspective, it is expensive to install, expensive to license, expensive to operate, and has no audience.

Hat from here.

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8 thoughts on “More HD radio news”

  1. @Paul: Radio World was the first to pick up this story, that I saw. I am always amused that IBOC proponents have nothing concrete to say, as I was attacked in the comment section. It certainly was not the first time, as it goes with the territory. It is funny, as you pointed out, the ignorance of much of the general media. Gorman used to point out how iBiquity has much of the trades and general media on their payroll to preach the word. The Washington Post and Wall Street Journal are prime examples. As I have pointed out before, HD Radio’s adjacent-channel interference really doesn’t offer “more radio stations”.

  2. @Pham, No, analog broadcasting is alive and well in the radio business. Television completed a transition to digital TV (all except low power TV and translators) a couple of years ago. As far as HD radio goes, adoption has been spotty at best. The programming choices are not compelling enough, the public is unaware, the technology is flawed. Trying to squeeze digital radio into the existing AM/FM bands has been a mistake. They would have done much better had they set aside separate spectrum, fully tested the system, then marketed it to the public as something new.

    @Greg, you are correct. It seems, in spite of the spin doctors, the word is getting out.

  3. I’m guessing they’re trying to lead us to believe that signal quality is improved when listening to the HD version of the signal on an HD capable radio. While I have virtually no personal experience with HD radio (except hearing the analog hash), based on things I’ve read, I don’t think what they claim is entirely true, or even remotely close.
    I’ll mention one example from when I was first learning about a “new thing” called “digital radio” (or whatever it was called at the time, before IBOC/HD/Ibiquity was even known to more than a select few). One of several things I expected from digital radio was a reliable, clean, high-fidelity signal (without compression artifacts), even in an area with low enough field strength (assuming you’re in an electrically quiet location like the middle of the deep south Pacific in winter) so that to even detect a trace on an analog radio with the same antenna and comparable circuitry, you HAD to use a BFO or QRSS CW detection mode or something similar. Also, with digital, I was expecting to be able to clearly hear the co-channel analog signal with a standard analog radio and hear any adjacent signals (no matter how weak) with any radio, even if my radio was fairly close to the tower as in these three photos, for example. (I also expected much better spectral efficiency (for example something like maybe 10-16 kHz of audio frequency response in stereo while only taking maybe 1 or at most 2 kHz of RF bandwidth), along with the brick-wall bandpass filters, as hinted at above, among other things.)
    Correct me if I’m wrong, but so far it doesn’t seem that the current incarnation of digital radio in the USA has achieved this?

  4. @Paul: At least in my mind, HD Radio was doomed from the start. In my Radio World article “HD Radio Faces Rocky Road” I touched upon things from who should have developed it, the affect of licensing costs right on down to the amount of demand (or lack thereof) there is for the technology. Those with operating radios are less likely to go out and buy hD-capable radio as the one they have operates fine, while younger people have little interest in radio thanks to the internet streams and iPod-like portable music players. It may take a little time but HD Radio will be keeping company with cart machines and AM Stereo exciters in the back of the engineering shack … or the dumpster!

  5. Then why waste time with HD radio if all it’s going to do is degrade the quality of the signal on the AM band,…or even FM for that matter? My analog radio works just fine,…who needs this HD crap? I agree with Bill,…HD radio components may end up in the back room with the old cart machines with a little time along with AM exciters. Better yet,..toss HD in the trash dumpster where it belongs. As a consumer,I have no use for it.
    Give me good ole analog radio ANY day of the week.

  6. I should take a few pictures of the C-QUAM exciters in various store rooms. There are several around.

  7. I sure hope HD Radio goes the way of C-QUAM! C-QUAM at least had the ability to sound fairly decent, unlike HD radio and all of it’s inherent bugs like adjacent channel (and even ON channel) interference, not to mention all of the nasty codec idiosyncrasies which requires shredding the input signal to keep from confusing the low bandwidth codec and causing it to generate artifacts.

    Blame K-street and large companies like Lucent Technologies for the legislation of crap like this. Any experienced radio or sound engineer would be able to point out all of the ails after reviewing the blueprints for such a poorly thought out system. Apparently there wasn’t any word from those types in Washington when these decisions were being made.

    From my viewpoint and my experience: HD Radio = waste of time and money!

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