What got you the DX bug?

Timed out. Here's the link. Remember to look at Page 32ff for the Kahn FCC-SSB article.

http://www.americanradiohistory.com...Section-8-NAB-Engineering-Fifth-Edition-8.pdf

Somewhere, the original FCC-SSB designation for Full Carrier Compatible Single Sideband has been lost. Perhaps the FCC objected to the acronym suggesting that the FCC officially sanctioned the system.

DavidEduardo said:

Platform motion was only noticeable in a motor vehicle going at highway and freeway speeds. At hiking speed, you would never notice it. The motion did not have to do with multipath (mountains and hills and buildings) but with phase issues at wavelength multiples (at least that is what their technical bulletins said...).

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Wish I had known that before dodging rattlesnakes in that canyon! But I never noticed any platform motion driving into or out of the canyon. Probably the last time I ever had a C-Quam radio in the car ----

C-Quam was like regular AM radio for radios that had it. It had amazing range. I remember hearing WFAN in stereo in SC; and hearing WLS during twilight in northeast GA, both in stereo. I don't remember any of my locals in Charleston having it (I think they dropped it in 80s or early 90s), but it probably had equal range to mono AM.

charlestondxman said:

HD AM is one of those cases where the new system is vastly inferior to the system it replaced.

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C-Quam was dead long before HD came on the scene. It did not work because it arrived too late, well after most of the music audience had migrated to FM. Those who left AM had the idea that AM sounded inferior, and nothing would get them back.

In any other industry, it would have been scrapped and C-Quam re-established as the standard years ago, and the designers of HD-AM would be out of a job.

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The "industry" wanted a digital system, not an analog one. The competition was perceived to be digital vs. analog, and reviving an analog system that had died a decade before was not an option. They also wanted a compatible AM system that could be a single chip solution.

Unfortunately radio has rather lemming-ish owners who have myopia and couldn't see past the high pressure sales pitch obviously given them.

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The radio industry funded iBiquity to take the existing digital radio development from Lucent (Bell Laboratories) and get it to market. So nobody sold the iBiquity product to radio since the larger radio companies were the initial providers of capital.

I wish industry people had the balls to do the same when this utter junk was pitched to them.

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"It may be junk, but it is our junk."

I think we would have a very different AM band today if C-Quam had been forcefully adopted 5 years before it was, required on all new radios, etc. We would have music on over 200 channels instead of music being relegated to the range limited FM band.

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C-Quam or one of the other four systems would have been adopted at the end of 1977 when AM radio still had about half of all listening and the improvement could have been noticed. But Leonard Kahn, AM radio's hangman, took legal action and held wide adoption back by half a decade, by which time AM was dead for music.

November 2006, I was 15 years old and I decided to listen to my dad's walkman. I was curious about a 107.1 station just a bit over the NJ/NY line in Rockland/Westchester.(WXPK Briarcliff Manor) I knew they played rock music.I lived outside Newark and the NYC signals were the only stations that were really known in my area. I found the station and I tilted the walkman the other way and received another station that played "Step Into Christmas" by Elton John. Curious, I waited a good 1-2 minutes to find where it came from (plenty of those waits to come with E Skip openings) but I heard 107.1 the Breeze and heard business ads from Monmouth/Ocean Counties. I was amazed, over the distance and discovered RadioLocator.Com. My next DX was 106.3 WHTG, 94.3 The Point, 95.9 The Rat from the same area. These are all stations that can be heard regularly, where I am.

I want to say overall, it was the push to try and find farther stations every day, was what kept me into the hobby and then later discovering the affect of tropo and e-skip.

rbrucecarter5 said:

"It may be junk, but it is our junk."

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It was the industry that persuaded the commission to standardize it.
I love Eureka-147, DAB, and so do most of the world's regularity agencies.

rbrucecarter5 said:

But Leonard Kahn, AM radio's hangman, took legal action and held wide adoption back by half a decade, by which time AM was dead for music.

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In his defense, it is well established that his system was the best.
It was the only system in which a station's stereo coverage area
was equal to the station's monaural coverage area
and it had no undesirable artifacts.

At least we got cheap synchronous detection chips out of it
(now that worldband shortwave is a non-thing, anyway).

DAB is a better system for the consumer, but not so much for the broadcasters.
It levels the signal and bandwidth disparities between all AM and FM stations in an area, plus brings in a lot more competition.
Also, the listener can check to see what is currently playing on all other stations while listening to one,
and then go to any other station without having to wait an eternity for the station to lock.

I do not see how what you said about KH would be possible because all the other systems added phase,
frequency, or quadrature modulation components, while K-H only modulated the upper and lower sidebands independently.
And, as I said, the stereo coverage area matched the monaural coverage area, and
I cannot remember to which direction the balance shifted with asymmetrical modulation on C-Quam stations,
but there was definitely a 25% shift when the station transmitted 125% positive modulation.
I remember that as if it were just thirty years ago. Um, it was about thirty years ago!
My main concern with any technical standard is always how it handles the worst real-world situations best.

rbrucecarter5 said:

C-Quam was dead long before HD came on the scene. It did not work because it arrived too late, well after most of the music audience had migrated to FM. Those who left AM had the idea that AM sounded inferior, and nothing would get them back.



The "industry" wanted a digital system, not an analog one. The competition was perceived to be digital vs. analog, and reviving an analog system that had died a decade before was not an option. They also wanted a compatible AM system that could be a single chip solution.



The radio industry funded iBiquity to take the existing digital radio development from Lucent (Bell Laboratories) and get it to market. So nobody sold the iBiquity product to radio since the larger radio companies were the initial providers of capital.



"It may be junk, but it is our junk."



C-Quam or one of the other four systems would have been adopted at the end of 1977 when AM radio still had about half of all listening and the improvement could have been noticed. But Leonard Kahn, AM radio's hangman, took legal action and held wide adoption back by half a decade, by which time AM was dead for music.

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Interesting how that looked like a post from me, commenting on myself!

Agree with the assessment on Leonard Kahn - superior system, but he doomed AM stereo, along with music on the AM band. Better system at the wrong time. The worst possible time for AM.

You did misspeak about one thing - C-Quam could have been programmed into HD chips and you would still have a one chip solution. In fact, a lot of people report HD radios decoding C-Quam. Some have the algorithm, some don't.

As for digital vs. analog, we both know consumers are woefully ignorant of technology. When HD-AM started to crash and burn, broadcasters could have simply switched to C-Quam, knowing it decoded in at least some HD radios - and called in "HD-AM 2". No consumer would have known, or cared, that it wasn't digital. At least AM would have had a path to better sound and stereo. Too bad it would be Rush Limbaugh with stereo musical beds and stereo commercials. NOT very compelling. Still better than stereo sports talk, though.

The ship has sailed for AM, stations will linger for decades, but I see more and more radios deleting the band as time goes on. Will FM be far behind as the band gets more cluttered with low power translators and LPFMs that don't have any range but chew up bandwidth and mix together at the first sign of tropo? Let's re-make FM in the image of AM, since that worked so well for the AM band.

ai4i said:

DAB is a better system for the consumer, but not so much for the broadcasters.
It levels the signal and bandwidth disparities between all AM and FM stations in an area, plus brings in a lot more competition.
Also, the listener can check to see what is currently playing on all other stations while listening to one,
and then go to any other station without having to wait an eternity for the station to lock.

I do not see how what you said about KH would be possible because all the other systems added phase,
frequency, or quadrature modulation components, while K-H only modulated the upper and lower sidebands independently.
And, as I said, the stereo coverage area matched the monaural coverage area, and
I cannot remember to which direction the balance shifted with asymmetrical modulation on C-Quam stations,
but there was definitely a 25% shift when the station transmitted 125% positive modulation.
I remember that as if it were just thirty years ago. Um, it was about thirty years ago!
My main concern with any technical standard is always how it handles the worst real-world situations best.

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Read pages 32ff, and you will see how independent sidebands HAVE to phase modulate the carrier to some degree. It's the "secret" Leonard apparently never revealed, and explained why the Motorola chip would decode it as long as something "falsed" the chip, like a pilot tone. With two sidebands, you have two spinning vectors, and when R .NE. L, there is phase modulation of the carrier, similar to Magnavox. It doesn't matter how it was marketed.

http://www.americanradiohistory.com...Section-8-NAB-Engineering-Fifth-Edition-8.pdf

ai4i said:

...and so do most of the world's regularity agencies.

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OMG...I cannot believe that I let this one out, I am usually very careful.
We become much too trusting of and loving toward our spell checkers.
These government regulators do not control anyones digestion.

I was about ten years old. My parents had bought me a transistor radio in the shape of a Pittsburgh Steelers football helmet. I was lying in bed playing with it one night when I came across the play-by-play of an ABA Kentucky Colonels game on WHAS, Louisville. I was fascinated. Then I found Bob Chase and Ft. Wayne Komet Hockey on WOWO, and a station in Chicago (WLS) that sounded a whole lot like my local rock-and-roll stations, KQV and 13Q. I was pretty much hooked after that.

FreddyE1977 said:

I was about ten years old. My parents had bought me a transistor radio in the shape of a Pittsburgh Steelers football helmet. I was lying in bed playing with it one night when I came across the play-by-play of an ABA Kentucky Colonels game on WHAS, Louisville. I was fascinated. Then I found Bob Chase and Ft. Wayne Komet Hockey on WOWO, and a station in Chicago (WLS) that sounded a whole lot like my local rock-and-roll stations, KQV and 13Q. I was pretty much hooked after that.

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WLS & KQV were both ABC owned at the time you were listening.

When Rick Sklar was given control over all the music on the ABC O and Os, that's when they completely stopped breaking records, and WLS became the "World's Last Station" to play new releases. The ABC O and O's became not Contemporary, but "Recent Recurrent" stations. WLS adding a track was the signal to other Contemporary stations to drop it off the Current charts and into Recent Recurrents. He said it was the lawyers who told him to do that, to avoid accusations of DJ "promotional misconduct" (my term).

DavidEduardo said:

Where there is mostly free broadcasting...there is zero interest in DAB.

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Canada embraced it for a while,
possibly with an eye on expanding the number of CBC offerings,
but they never gave it enough of a chance.

Outside of Toronto there was very little, if any interest or attempt to use DAB. I know 1050 CHUM used it for a while and even advertised it. I don't even know if it was ever used here in Ottawa. It was hard to find a receiver, and with little demand for one, the few stations that did use it shut it off after a couple of years, with the licenses for DAB finally pulled a few years ago. I kind of wish I had a chance to try it but could never find a receiver. It was much easier to find an AM stereo receiver in Canada in the 80's than DAB when it was in use.

mimo said:

I kind of wish I had a chance to try it but could never find a receiver.
It was much easier to find an AM stereo receiver in Canada in the 80's than DAB when it was in use.

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To the end user,
I believe that it works very much like satellite radio,
but with only station names and no channel numbers.

I kind of wish I had a chance to try it out,
like if I ever make it to London.

DavidEduardo said:

The only governments that favor DAB are in nations where the most significant broadcasters are state entities. Finland, England, etc. Where there is mostly free broadcasting, such as all of Latin America, there is zero interest in DAB.

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On one of my visits to our daughter during the 11 years that she lived in London, she was very excited to have won a DAB portable radio in some sort of BBC phone in contest. Long story short, she was very disappointed when the radio arrived. She didn't see any advantage whatsoever to listening in DAB mode. To her ears the quality sounded almost exactly the same as MW and FM stereo. "What's the point?" were her exact words. After she let me play with the radio, I couldn't answer that.

In addition to BBC (radio 3 IIRC), most of her radio listening was online NPR, WDRV (Chicago classic rock FM), and Sirius FM using my login credentials. All of which produced better audio and fewer dropouts.