'HD' Radio - That Didn't Last Long

[dumber than a box of hair]

So many questionable decisions have been made, on the technical, as well as the regulatory, and programming sides of radio over the past 30 years, or so, it almost appears that the powers that be have been "chasing" listeners away from the medium! Hmmm?

It's not just a matter of bad decisions. It's the concept, which radio executives can't seem to get through their thick skulls, that every new tech automatically attracts new listeners or keeps current ones. Unless that new tech yields a huge benefit for the listener (FM supplanting AM for music, for example), they should have learned their lesson from the failure of AM stereo to save AM from becoming a medium full of who-can-shout-the-loudest talk hosts.

Whatever the benefits and shortcomings of HD, one thing is for sure, after ten years of trying: It's not going to make a material difference to listeners. The only thing that consistently attracts listeners and keeps them is programming.

 

[nfladxer]

So many questionable decisions have been made, on the technical, as well as the regulatory, and programming sides of radio over the past 30 years, or so, it almost appears that the powers that be have been "chasing" listeners away from the medium! Hmmm?

It's not just a matter of bad decisions. It's the concept, which radio executives can't seem to get through their thick skulls, that every new tech automatically attracts new listeners or keeps current ones. Unless that new tech yields a huge benefit for the listener (FM supplanting AM for music, for example), they should have learned their lesson from the failure of AM stereo to save AM from becoming a medium full of who-can-shout-the-loudest talk hosts.

Whatever the benefits and shortcomings of HD, one thing is for sure, after ten years of trying: It's not going to make a material difference to listeners. The only thing that consistently attracts listeners and keeps them is programming.

I agree, beyond anything technical, programming IS the key! I have an excellent HD tuner, and enjoy the listening experience, although I haven't heard it in a moving vehicle. The alternate programming choices available on the HD sub-channels, in this Top 50 market, are limited, at best. While I realize there's got to be an economic incentive for broadcasters to offer niche programming, the fact that they haven't, in any significant way, pretty much says it all. Except for some translator deals, there doesn't seem to be much of a reason for most operators to establish new HD-2's, etc. With all the new electronic products being rolled out almost daily, the general listening public has not really had much of a reason to embrace this technology. No Rocket Science here: Radio has got to give them that REASON to want to listen, unfortunately, that hasn't happened, and HD seems to be lost in the shuffle, just like AM Stereo was!

 

[spunker88]

As I've said before, signal quality when HD is working is not perceptible to my ears to be any better quality than analog FM so without desirable content there is no point in having it.

If anything HD will sound worse since it uses a lossy digital audio format. I believe the spec for HD radio allows for higher frequency response than FM, but of the several HD stations I've sampled from my XDR-F1HD, all were cutting off around 15khz giving the same frequency response as FM.

I guess if you have a subchannel that has no analog station, then it may be worth it, but I would never want to listen to an HD-1.

 

[davideduardo]

If you're in Phoenix, how well does KAZG 1440 Scottsdale come in?

KAZG is not really "low power" by US standards. It's basically a 5 kw daytimer (if you don't count the 21 big night time watts). It recently installed a new Nautel transmitter; when I drove through Phoenix a week or so ago (using the loop from the 10 to the 17) I spot checked it in the NW quadrant of the market, and it sounded quite good, signal wise.

A better test for someone in Tempe would be trying to get the 1190 in Tolleson or the 710 from Black Canyon City.

 

[landtuna]

A better test for someone in Tempe would be trying to get the 1190 in Tolleson or the 710 from Black Canyon City.

From my location off Warner Road midway between I-10 and Loop 101 I cannot get a listenable signal from KAZG from car, home stereo or portable in my house. I can hear it during the daytime but it is filled with static. Once the lamptimer kicks in it disappears completely.

Taking the Loop 101 (east side) north the signal improves once I cross the Salt River and becomes listenable all the way until the highway turns west above Bell Road. It isn't a great quality signal but it is listenable.

I'll try to remember to dial in 1190 and 710 and see how I hear them.

 

[KB1OKL]

Is it one of those little "stubby" antennae just above the rear windshield?

If it is, it's no wonder you're having trouble. I still can't figure out how anyone could even consider those things adequate for analogue reception, let alone data. Even the ancient wires-in-the-windshield dipole I had in the Bronco worked better than some of these things they have now.

If you can, try putting a real aerial (i.e. a whip) on the car and wire it into the radio instead.

I have one of those stubby antennas above my rear window, it actually works great, it's not the antenna, it's HD that causes lousy reception as we all already know. BTW i don't think the term "aerial" has been in use since Ma and Pa Kettle went off the air.

 

[Tom Wells]

Is it one of those little "stubby" antennae just above the rear windshield?

If it is, it's no wonder you're having trouble. I still can't figure out how anyone could even consider those things adequate for analogue reception, let alone data. Even the ancient wires-in-the-windshield dipole I had in the Bronco worked better than some of these things they have now.

If you can, try putting a real aerial (i.e. a whip) on the car and wire it into the radio instead.

I have one of those stubby antennas above my rear window, it actually works great, it's not the antenna, it's HD that causes lousy reception as we all already know. BTW i don't think the term "aerial" has been in use since Ma and Pa Kettle went off the air.

"Works great" is not a quantitative analysis when discussing the laws of physics.
RF signals have an actual physical dimension, and when making a transmitting antenna it is absolutely necessary to respect the
electrical wavelength as represented in the physical antenna, if being effective is an issue.

A 31 inch whip is just about perfect for FM, and shorter "more sytlish" antennas will "sorta" work, a lttle better with pre-amps, but then
there's other issues with noise pickup, etc. Such an antenna has NONE of the physical characteristics needed to a good job with MW AM,
where the physical wavelength is 100 times longer. 100 mhz equals 1 meter and 1 mhz equals 100 meters, plus/minus propogation delay in
a physical medium (wire) vs free space. NO one has yet found any real way to disrespect the laws of physics, but they can
sell products that claim to work acceptably, if there are those who are willing to believe.
Try exiting the freeway into a cloverleaf ramp at ten times the suggested speed and tell us how well your vehicle hangs onto the curve.

 

[Chuck]

A 31 inch whip is just about perfect for FM, and shorter "more sytlish" antennas will "sorta" work, a lttle better with pre-amps, but then
there's other issues with noise pickup, etc. Such an antenna has NONE of the physical characteristics needed to a good job with MW AM,
where the physical wavelength is 100 times longer. 100 mhz equals 1 meter and 1 mhz equals 100 meters, plus/minus propogation delay in
a physical medium (wire) vs free space. NO one has yet found any real way to disrespect the laws of physics, but they can
sell products that claim to work acceptably, if there are those who are willing to believe.
Try exiting the freeway into a cloverleaf ramp at ten times the suggested speed and tell us how well your vehicle hangs onto the curve.

Well, I'm as big a fan of mathematics as it gets, but I have to say that the little antennas on my 2007 Chevy Tahoe and my 2012 Buick work very well on analog radio. I'm not sure what black magic has been applied, but this is nothing like the crappy "in the windshield" designs of the 1980's. Whatever it is, it is perfectly acceptable to 99.9% of all listeners, as long as the signal is analog.

 

[tomservo]

When the amplified antenna in my VW worked, it also had satisfactory reception. The FM was slightly above average (with a 31" whip on a GM vehicle with a Delco radio being my idea of a nearly excellent setup) and the AM was noticeably better.

Better still is the stock radio in the Mazda, which has no antenna visible anywhere; no shark fin, no window surround, no whip. It trades audio response on AM for incredible sensitivity; it's the only radio I have that can pick up WINK reliably from Fort Myers in my own town, 14 miles north of the beach. In Alabama. (440 miles over mostly salt water.) The FM isn't overly selective but is very, very sensitive. The lack of a visible antenna on these two cars doesn't seem to impede reception to any noticeable degree. (Well it does on the VW now since the amp corroded.)

 

[landtuna]

Took another drive in the Genny last night - this time at night and in a different direction (away from the towers actually) and had much more positive results.

Both 94.5 and 99.9 HD-2's were on the air and both were playing what they advertised. The quality of their music wasn't any different than what is played on their main signals but it wasn't any worse either and the lack of commercials was nice.

My trip carried me eastward from the Loop 101 along the Loop 202 out about ten miles or so and there were no noticeable drop-outs coming or going. So I'm not sure if it was the area I was in that had better propagation or perhaps both stations were having trouble the last time I tried picking them up.

At any rate, it appears it was not the car or its antenna system malfunctioning last time.

Testing continues.....

 

[kenglish]

Maybe it was because the (little-bitty) antenna is at the back of your car, so the signal is better when you drive away from the towers.

 

[landtuna]

Maybe it was because the (little-bitty) antenna is at the back of your car, so the signal is better when you drive away from the towers.

Except that the signal was good both coming and going.

If I remember from my old RF propagation tests on my navy destroyer the RF will tend to follow magnetic properties so, in the case of the antenna being at the rear of the car, the strongest signals will be towards the front in kind of an egg shaped pattern with the narrow part to the rear.

 

[KB1OKL]

Is it one of those little "stubby" antennae just above the rear windshield?

If it is, it's no wonder you're having trouble. I still can't figure out how anyone could even consider those things adequate for analogue reception, let alone data. Even the ancient wires-in-the-windshield dipole I had in the Bronco worked better than some of these things they have now.

If you can, try putting a real aerial (i.e. a whip) on the car and wire it into the radio instead.

I have one of those stubby antennas above my rear window, it actually works great, it's not the antenna, it's HD that causes lousy reception as we all already know. BTW i don't think the term "aerial" has been in use since Ma and Pa Kettle went off the air.

"Works great" is not a quantitative analysis when discussing the laws of physics.
RF signals have an actual physical dimension, and when making a transmitting antenna it is absolutely necessary to respect the
electrical wavelength as represented in the physical antenna, if being effective is an issue.

I guess I should have said that my car radio seems to work as well as any other I've had that have had whip antennas, my main complaint with it is the AM muffled sound, the reception is fine, it's just not listenable because the filter in it is so narrow. I'm a radio fan and DXer and know when a radio is insensitive, of course the radio in the car is a good one, a Blaupunkt. On FM it seems to work as well as my other car does that has a whip.

 

[landtuna]

A better test for someone in Tempe would be trying to get the 1190 in Tolleson or the 710 from Black Canyon City.

I cannot receive either 1190 or 710 from my house in Tempe. 1190 is just hash and 710 appears to be a Spanish-language signal from far, far away. I can't hear it well enough to make out the calls.

Too bad I don't still have my SW set and long wire. It was pretty good getting AM's and could filter out the OBOC hash fairly well.

 

[Darth_vader]

"I'm not sure what black magic has been applied, but this is nothing like the crappy "in the windshield" designs of the 1980's."

Yeah, for one thing, those (air quotes) "crappy" wires-in-the-windshield dipole aerials (yes) actually were somewhat better wavelength-matched than a shark-fin aerial could ever be. I had rather decent results with the one in the bronco, which actually had solid copper wires embedded in the glass (not just traces printed on the surface.)

The little "shark fin" aerials are like trying to listen to VHF FM with an 800 MHz cell phone aerial. It "kinda" works but not very well because they're not electrically matched. (Just go back and reread what Tom Wells said in his previous post; I've been up 32 hours now and I'm tired.)

Part of your problem could also be that the radio's front-end might just be dead. Shoddy workmanship, not the "Ibiquity-versus-no-Ibiquity" rot.

 

[Kmagrill]

The windshield dipoles worked almost as well as a rod, if you were driving toward the station. The problem is that they were much more directional, so when 90 degrees off axis, they were noticeably poorer performing than a rod. When driving away from the station, the embedded antennas also suffered from poor performance due to the body of the vehicle blocking some of the signal.

These sharkfin designs are mostly fractal antennas that, supposedly, have amazing performance for the size. Fractal antennas are patented, but there are still lots of unlicensed, knock-offs around. A full sized rod antenna will still outperform a mini-fractal, but the performance difference isn't as big as one might think. Also, a full sized fractal should outperform a dipole or rod which is why many new cellphones use fractal antennas. It would be interesting to try designing a full sized fractal for FM to see how it compared.....

 

[Chuck]

The windshield dipoles worked almost as well as a rod, if you were driving toward the station. The problem is that they were much more directional, so when 90 degrees off axis, they were noticeably poorer performing than a rod. When driving away from the station, the embedded antennas also suffered from poor performance due to the body of the vehicle blocking some of the signal.

These sharkfin designs are mostly fractal antennas that, supposedly, have amazing performance for the size. Fractal antennas are patented, but there are still lots of unlicensed, knock-offs around. A full sized rod antenna will still outperform a mini-fractal, but the performance difference isn't as big as one might think. Also, a full sized fractal should outperform a dipole or rod which is why many new cellphones use fractal antennas. It would be interesting to try designing a full sized fractal for FM to see how it compared.....

Here is a man who knows what he is talking about. Thanks for joining in.

A full size fractal antenna for 100 MHz would probably work great, but it would be a little "awkward" glued on the roof of your Prius. ;D

 

[landtuna]

A half day spent driving family around town to "see the sights" yesterday revealed no dropouts or other signal disruption from my HD2 stations. I was on both 94.5 and 99.9 HD2 and both were flawless.

Having said that, the audio quality is still indistinguishable from that of one of the better FM's in the Valley.

 

[rbrucecarter5]

Here is a man who knows what he is talking about. Thanks for joining in.

A full size fractal antenna for 100 MHz would probably work great, but it would be a little "awkward" glued on the roof of your Prius. ;D

Want to approximate a fractal and get a huge boost out of your whip antenna? Wrap some conductive tinsel around it. An old trick that really does work! The only problem is finding tinsel that is really conductive.

 

[Darth_vader]

Can you even still get real aluminum tinsel these days? All I've ever seen is that shiny plastic crap (about as conductive as a strip of masking tape!)

My Grampa actually did that for the shortwave aerial on his JVC 990 Deluxe console stereo. Eight feet of genuine, vintage 1962 aluminum tinsel running up the corner of the living room walls.