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"Heard by few, touted by many"

P

PocketRadio

"Heard by few, touted by many"

"Broadcasters are betting that unique programming, local flavor and higher sound quality will entice people to turn off their iPods, cancel their satellite subscriptions and turn on their radios." :D

Time to to rip out our in-dash Satellite Radio and replace it with an ugly in-dash HD Radio, that gets problematic reception due to the Doppler Effect and the 1% HD/IBOC power levels, and volume changes due to the parallel analog/digital audio processing ! :D

"HD Radio reaches only about 450,000 listeners weekly, according to the radio measurement service Bridge Ratings"

Bridge Ratings assumes 3 listeners per radio - this figure is the 150,000 HD radios sold (minus returns) X 3 listeners/radio.

"Digital radio supporters expect its popularity to grow quickly..."

It's all a big shill and lie, in an attempt to please Wall Street:

http://www.google.com/trends?q="hd+...odcast&ctab=0&geo=US&geor=all&date=all&sort=0

"For all the touted benefits, HD Radio has plenty of critics, especially in blogs and online discussion boards. They question whether the technology works, whether it's worth the cost, and who stands to gain from its success... We're very skeptical this is going to be accepted if (listeners are) going to get alternate versions of what they've already rejected."

Yea, we are getting noticed ! :D

"But many supporters dismiss the critics, saying the technology is proven, the content already is more diverse, and the public will benefit. They're just waiting for the signals to be sent and the dials to turn."

Hasn't it been long enough - HD radios are not selling, Gen Y laughs at the concept of HD Radio (we laugh at it, too), and conversions to HD/IBOC are slowing. HD/IBOC signals have been sent since 2002, and the first HD radio was sold in 2004.

http://www.kentucky.com/109/story/93633.html
 
"Doppler effect" is somebody's fantasy. For doppler effect to be significant, the car would actually have to travel at a large percentage of the speed of light, not a tiny fraction of the speed of sound.

A car travels at a max of perhaps 65 miles per hour (legally, anyway). Radio waves travel at 186,000 miles per second. This should keep you busy...what tiny percentage of the speed of radio waves is the speed of a car? The answer should give you a feel for how significant "doppler effect" is for HD, or any other radio. With such high regard for science, you really should work for the Bush Administration. This "science" is up there with the "science" from the early days of cd, when so called "research" "demonstrated" that playing cds can damage your audio system, that digital audio itself is "harmful". I remember reading one guy that even Stereophile called Looney Tunes who said playing digitally mastered LPS(!) could crack the bearings on your turntable. Your "science" is right up there! Good work, Pocket. As usual, you've enlightened us so.

Don't you realize how much creedance you give to the other side of the argument by making such "reasoned, well grounded" arguments? PLEASE keep it up!

Oh...just one question for the "scientific mind" that you've again proven yourself to be. Why wouldn't said "doppler effect" also affect satellite radio, wi-fi, wi-max, or any other rf technology used in moving cars, since ALL RADIO WAVES at ALL FREQUENCIES move at the same speed...the speed of LIGHT!!!!????
 
Mike Walker said:
"Doppler effect" is somebody's fantasy. For doppler effect to be significant, the car would actually have to travel at a large percentage of the speed of light, not a tiny fraction of the speed of sound.

A car travels at a max of perhaps 65 miles per hour (legally, anyway). Radio waves travel at 186,000 miles per second. This should keep you busy...what tiny percentage of the speed of radio waves is the speed of a car? The answer should give you a feel for how significant "doppler effect" is for HD, or any other radio. With such high regard for science, you really should work for the Bush Administration. This "science" is up there with the "science" from the early days of cd, when so called "research" "demonstrated" that playing cds can damage your audio system, that digital audio itself is "harmful". I remember reading one guy that even Stereophile called Looney Tunes who said playing digitally mastered LPS(!) could crack the bearings on your turntable. Your "science" is right up there! Good work, Pocket. As usual, you've enlightened us so.

Don't you realize how much creedance you give to the other side of the argument by making such "reasoned, well grounded" arguments? PLEASE keep it up!

Oh...just one question for the "scientific mind" that you've again proven yourself to be. Why wouldn't said "doppler effect" also affect satellite radio, wi-fi, wi-max, or any other rf technology used in moving cars, since ALL RADIO WAVES at ALL FREQUENCIES move at the same speed...the speed of LIGHT!!!!????
Click to expand...

"Duking It Out Over Datacasting" RWOnline

"Let's digress for a moment to consider that not all non-fixed digital receivers are created equal. Mobile and portable platforms each present their own design constraints. In the mobile case, the biggest problem is Doppler shift from the potentially high speed of the moving antenna. Space-diversity antennas may be used here, whereas these are not practical in most portable systems."

http://www.rwonline.com/reference-room/skippizzi-bigpict/05_rwf_pizzi_aug_1.shtml
 
PocketRadio said:
http://www.kentucky.com/109/story/93633.html
"Heard by few, touted by many"
Click to expand...

This is actually a pretty good article.

Yea, we are getting noticed ! :D
Click to expand...

And THIS is why it was lnked. Loonies take note. IN the eyes Pocketradio, this articles is showing how the Anti side is WINNING.

Opinions vary.

Clouseau


"But many supporters dismiss the critics, saying the technology is proven, the content already is more diverse, and the public will benefit. They're just waiting for the signals to be sent and the dials to turn."

Hasn't it been long enough - HD radios are not selling, Gen Y laughs at the concept of HD Radio (we laugh at it, too), and conversions to HD/IBOC are slowing. HD/IBOC signals have been sent since 2002, and the first HD radio was sold in 2004.
 
I emailed Jamie, the HD Radio reporter for this article, with the usual links and already heard back from him:

Subject: RE: "Heard by few, touted by many"
Date: 6/10/07 5:12:34 PM Mid-Atlantic Daylight Time
From: [email protected]
Reply To: ********@******

******,

Thanks for writing. I'll be keeping a close eye on how this turns out.

Have a good day!

Jamie G.
 
PocketRadio said:
I emailed Jamie, the HD Radio reporter for this article, with the usual links and already heard back from him:

Subject: RE: "Heard by few, touted by many"
Date: 6/10/07 5:12:34 PM Mid-Atlantic Daylight Time
From: [email protected]
Reply To: ********@******

******,

Thanks for writing. I'll be keeping a close eye on how this turns out.

Have a good day!

Jamie G.
Click to expand...

A perfect "Blow off" response, the same type I'd give your mindless ramblings.
 
HD Radio uses COFDM. COFDM has been proven to work very well for mobile reception, not just in the lab, but in the real world. The European DVB television system uses it (they laugh at the U.S., by the way, for using 8-VSB). The new Qualcomm mobile TV system for cell phones uses it. It's used for Minicam/ENG feeds. It holds up very well under varying multipath and Doppler shift conditions.

I had one of the first JVC HD Radios in my car. It didn't work well with my in-glass dipole antenna (which is highly directional), but speed did not affect reception of HD Radio stations, even as high as 70mph.
 
Doppler effect IS REAL. It's just that one must approach a large portion of the freakin' speed of sound for it to become significant. If you're goin' that fast in your car, you've got bigger problems than radio reception...like your liquified remains on the rear window ;)

I have subscribed to Radio World for more than 20 years. Sometimes their articles are very insightful, sometimes they're so poorly worded I can't understand the point they're trying to make, and sometimes their science is, well...science FICTION! Just as with any group of randomly selected people. Some would understand and grasp scientific concepts, some would believe in evolution, some would believe the Earth was 5,000 years old and George W. Bush was selected by Christ. Guess which group I give greater weight to!

The old Audio magizine being the one possible exception, there isn't any technical journal that I don't believe has occasionally gotten the science, or simply the facts wrong. No shocker. Human beings make mistakes.
 
Mike Walker said:
Doppler effect IS REAL. It's just that one must approach a large portion of the freakin' speed of sound for it to become significant. If you're goin' that fast in your car, you've got bigger problems than radio reception...like your liquified remains on the rear window ;)
Click to expand...

I've driven some pretty fast cars but never had to retune the radio from 98.1 to 98.0 or 98.2 to compensate for doppler effect. :)

The only time I've ever witnessed noticeable doppler shift to radio signals is using a scanner to tune military and amateur comms from an elliptical-orbit satellite. As the satellite approaches from over the horizon, the signal is shifted upward approximately 5 kHz (that's 0.005 MHz). After it passes overhead, the signal continues to slide downward to -5 kHz shift before it quickly drops over the horizon.
 
Philip J. Smith said:
The only time I've ever witnessed noticeable doppler shift to radio signals is using a scanner to tune military and amateur comms from an elliptical-orbit satellite. As the satellite approaches from over the horizon, the signal is shifted upward approximately 5 kHz (that's 0.005 MHz). After it passes overhead, the signal continues to slide downward to -5 kHz shift before it quickly drops over the horizon.
Click to expand...

Funny we don't have this "Doppler Effect" causing problems on Sirius.

Clouseau
 
Mike Walker said:
Doppler effect IS REAL. It's just that one must approach a large portion of the freakin' speed of sound for it to become significant. If you're goin' that fast in your car, you've got bigger problems than radio reception...like your liquified remains on the rear window ;)
Click to expand...

"Doppler Radars"

"You can hear the Doppler effect when a car or train is approaching you while sounding a horn. The horn pitch changes to a lower frequency once the car or train passes you."

http://www.wkrg.com/servlet/Satellite?pagename=WKRG%2FMGArticle%2FKRG_BasicArticle&c=MGArticle&cid=1031777069474&path=!weather!education

Wrong - you don't have to be going the speed of sound for the Doppler Effect !
 
Mike Walker said:
Doppler effect IS REAL. It's just that one must approach a large portion of the freakin' speed of sound for it to become significant. If you're goin' that fast in your car, you've got bigger problems than radio reception...like your liquified remains on the rear window ;)

I have subscribed to Radio World for more than 20 years. Sometimes their articles are very insightful, sometimes they're so poorly worded I can't understand the point they're trying to make, and sometimes their science is, well...science FICTION! Just as with any group of randomly selected people. Some would understand and grasp scientific concepts, some would believe in evolution, some would believe the Earth was 5,000 years old and George W. Bush was selected by Christ. Guess which group I give greater weight to!

The old Audio magizine being the one possible exception, there isn't any technical journal that I don't believe has occasionally gotten the science, or simply the facts wrong. No shocker. Human beings make mistakes.
Click to expand...

"Radar gun"

"A radar gun is a small Doppler radar used to detect the speed of objects. A radar gun does not return information regarding the object's position. It relies on the Doppler Effect applied to a radar beam to measure the speed of objects it is pointed at."

http://en.wikipedia.org/wiki/Radar_gun

Yea guys, the Doppler Effect, as it relates to moving vehicles, is all make-believe ! :D
 
PocketRadio said:
Mike Walker said:
Doppler effect IS REAL. It's just that one must approach a large portion of the freakin' speed of sound for it to become significant. If you're goin' that fast in your car, you've got bigger problems than radio reception...like your liquified remains on the rear window ;)

I have subscribed to Radio World for more than 20 years. Sometimes their articles are very insightful, sometimes they're so poorly worded I can't understand the point they're trying to make, and sometimes their science is, well...science FICTION! Just as with any group of randomly selected people. Some would understand and grasp scientific concepts, some would believe in evolution, some would believe the Earth was 5,000 years old and George W. Bush was selected by Christ. Guess which group I give greater weight to!

The old Audio magizine being the one possible exception, there isn't any technical journal that I don't believe has occasionally gotten the science, or simply the facts wrong. No shocker. Human beings make mistakes.
Click to expand...

"Radar gun"

"A radar gun is a small Doppler radar used to detect the speed of objects. A radar gun does not return information regarding the object's position. It relies on the Doppler Effect applied to a radar beam to measure the speed of objects it is pointed at."

http://en.wikipedia.org/wiki/Radar_gun

Yea guys, the Doppler Effect, as it relates to moving vehicles, is all make-believe ! :D
Click to expand...

I guess that's why most officers must scrape the remains of each speeder they get with those radar guns if we go by Mikes assessment of the doppler effects.

Good thing Mike is in radio and not designing airplanes or rocket ships or we'd all have a mess on our hands!

Radiopilot
 
PocketRadio said:
Mike Walker said:
Doppler effect IS REAL. It's just that one must approach a large portion of the freakin' speed of sound for it to become significant. If you're goin' that fast in your car, you've got bigger problems than radio reception...like your liquified remains on the rear window ;)
Click to expand...

"Doppler Radars"

"You can hear the Doppler effect when a car or train is approaching you while sounding a horn. The horn pitch changes to a lower frequency once the car or train passes you."

http://www.wkrg.com/servlet/Satellite?pagename=WKRG%2FMGArticle%2FKRG_BasicArticle&c=MGArticle&cid=1031777069474&path=!weather!education

Wrong - you don't have to be going the speed of sound for the Doppler Effect !
Click to expand...

Rarely have you two made such complete fools out of yourselves as this time.

A complete set of calculations has already been provided to you as to the effect of frequency shift on radio waves.

RP, as an aviation engineer, I would suspect you know better and are just playing around. Pocket OTOH.....

Radio travels at the speed of light. 186,000 Miles a second A car traveling at 60 MPH goes 1/60th of a mile in a second. That's a 1:11160000 ratio or a "Doppler shift" of 0.00000896 %.

At 99 MHz that's a change of .0008709 MHz. Most analog transmitters would be envious of this performance.

Perhaps a more graphical explanation is in order. One of the best ways to demonstrate how much Dopler effect there is on radio wave in a moving car is to use something that moves as fast as Radio waves as an example. How about your eyes?

Have you ever noticed that when you drive Towards a white object really fast it get's a reddish hue? And how if you look at it while driving away from it it's a little purple? Many times you need to try this several dozen times to really see it. Maybe you should get your keys...

Well there you go. That's "Doppler Shift". Right before your eyes.

Some people report being able to hear this on the radio as well. Remember how WABC records always seemed to be really fast? Doppler effect again.

Wonder why it doesn't do it anymore?

Must be global warming.

Pocket, you never cease to amaze me.:) and RP... You're kidding, right?

Clouseau
 
clouseau said:
Have you ever noticed that when you drive Towards a white object really fast it get's a reddish hue? And how if you look at it while driving away from it it's a little purple? Many times you need to try this several dozen times to really see it. Maybe you should get your keys...
Click to expand...

LMAO! :D
 
clouseau said:
PocketRadio said:
Mike Walker said:
Doppler effect IS REAL. It's just that one must approach a large portion of the freakin' speed of sound for it to become significant. If you're goin' that fast in your car, you've got bigger problems than radio reception...like your liquified remains on the rear window ;)
Click to expand...

"Doppler Radars"

"You can hear the Doppler effect when a car or train is approaching you while sounding a horn. The horn pitch changes to a lower frequency once the car or train passes you."

http://www.wkrg.com/servlet/Satellite?pagename=WKRG%2FMGArticle%2FKRG_BasicArticle&c=MGArticle&cid=1031777069474&path=!weather!education

Wrong - you don't have to be going the speed of sound for the Doppler Effect !
Click to expand...

Rarely have you two made such complete fools out of yourselves as this time.

A complete set of calculations has already been provided to you as to the effect of frequency shift on radio waves.

RP, as an aviation engineer, I would suspect you know better and are just playing around. Pocket OTOH.....

Radio travels at the speed of light. 186,000 Miles a second A car traveling at 60 MPH goes 1/60th of a mile in a second. That's a 1:11160000 ratio or a "Doppler shift" of 0.00000896 %.

At 99 MHz that's a change of .0008709 MHz. Most analog transmitters would be envious of this performance.

Perhaps a more graphical explanation is in order. One of the best ways to demonstrate how much Dopler effect there is on radio wave in a moving car is to use something that moves as fast as Radio waves as an example. How about your eyes?

Have you ever noticed that when you drive Towards a white object really fast it get's a reddish hue? And how if you look at it while driving away from it it's a little purple? Many times you need to try this several dozen times to really see it. Maybe you should get your keys...

Well there you go. That's "Doppler Shift". Right before your eyes.

Some people report being able to hear this on the radio as well. Remember how WABC records always seemed to be really fast? Doppler effect again.

Wonder why it doesn't do it anymore?

Must be global warming.

Pocket, you never cease to amaze me.:) and RP... You're kidding, right?

Clouseau
Click to expand...

Ummm, but doesn't the shift go the other way? Blue on closing distance, red shift on increasing distance?

I don't believe the issue is with frequency shift, more an issue with slew rate, and whether the "shift" can degrade the "sharpness" of the corners
of the "square wave" digital. In this case it's not a problem AT THE DATA RATE CHOSEN. A higher data rate would eventually find this limitation sooner.
As noted in ibiquity's reference material, it probably only means that jet airplanes can't copy HD.
It is for our purposes, a theoretical footnote regarding a limit on performance, which probably has a good deal with the rates used.
 
Tom Wells said:
Ummm, but doesn't the shift go the other way? Blue on closing distance, red shift on increasing distance?
Click to expand...

Good Question :)

Where's Beakman???

Upon furthur review. YOU ARE CORRECT, SIR!! (But I guess you actually knew that.)

I confess I always thought that since we Abbreviate the visible spectrum as ROYGBIV that Red was the Highest Freq and Violet was the shortest.

I was backwards. Shame on the rest of the class for not noticing. :)

Now where's the wiseguy that says "I didn't see the color change because it was backwards???" :)

Thanks for the correction, Tom.

Clouseau
 
I bet someone is driving really fast out there, trying to verify this for us.
Not on the NJ turnpike, I hope.
There's some roads in Montana that might be a good place to check this.
Somebody with a Learjet, tell us what speed HD radio works up to!
Do Learjets have windshield antennas, or 31" mast antennas for broadcast signals?
 
Tom Wells said:
Do Learjets have windshield antennas, or 31" mast antennas for broadcast signals?
Click to expand...

OK. Now I'M

LMAO! :)

Clouseau
 
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