Wonder what's going on here?

[stacker]

www.wrathofkahn.org




[NOTE-url corrected by Radio-Info as a courtesy to other users]

 

[dumber than a box of hair]

At the moment, nothing, because the site appears to be down.

 

[stormy01]

Well - if the site was more organized and Kahn wasn't spouting so much vitriol about "HD" IBOC, and point people more clearly to his CAM-D system, then perhaps the guy would get more traction for CAM-D. He needs to offer his alternative system in a more compelling way, he spends way more time bashing "HD" IBlOCk than promoting his product/system.

On this page: http://www.wrathofkahn.org/ Kahn talks about pricing, scroll down to: "NOW SOME GOOD NEWS AND SOME BAD NEWS RE PRICING" ...However, he doesn't present it too well, no pictures of his equipment or installations, the product should have its own site if he wants to sell it! (duh, basic marketing) He does offer some off-air recordings of his system on the website and he names the 4 stations that use his CAM-D system [if you should be so lucky to be within range of one of them and have a CAM-D receiver of course)

There is certainly a clearer explanation here: http://en.wikipedia.org/wiki/CAM-D

 

[TheBigA]

The key fact here is that this system still requires consumers to buy new radios. That is simply NOT going to happen. The public will not be going out en masse and replacing their old radios with new ones, regardless of the benefits in the new radios. There simply is not that much upside. Satellite radio is your best example. They offer digital audio, commercial-free music, and over a hundred different channels of programming. After 7 years and billions of dollars, they have less then 20 million subscribers. I'd call that a failure. It's not a function of the content, because the satellite companies overspent on content. It's not a function of the commercials, because the music channels are commercial free. It's not a function of the audio quality. None of that matters to the consumer. They simply aren't interested in replacing their radios. The old ones work just fine. Unless someone can come up with a way to change analog to digital without replacing the receivers, it's not going to succeed.

 

[audioguy]

The key fact here is that this system still requires consumers to buy new radios. That is simply NOT going to happen. The public will not be going out en masse and replacing their old radios with new ones, regardless of the benefits in the new radios. There simply is not that much upside. Satellite radio is your best example. They offer digital audio, commercial-free music, and over a hundred different channels of programming. After 7 years and billions of dollars, they have less then 20 million subscribers. I'd call that a failure. It's not a function of the content, because the satellite companies overspent on content. It's not a function of the commercials, because the music channels are commercial free. It's not a function of the audio quality. None of that matters to the consumer. They simply aren't interested in replacing their radios. The old ones work just fine. Unless someone can come up with a way to change analog to digital without replacing the receivers, it's not going to succeed.

That is basically the same problem HD radio faces. Even if it worked perfectly (and it is very far from that level of performance), listeners don't really care that much about it. Their existing radios work well enough. The fact that radio isn't "digital" is not enough of a reason to trash the current system. I'm still scratching my head to figure out why the broadcast industry would want HD radio either-- why splinter the ad revenues any further?

The way I see it, there is only one way that digital radio will succeed, and that is to make digital conversion mandatory, as has been done for TV. The problem is that the situation for radio is different in several ways: First, there is presently no extra spectrum to give digital radio a "fresh start", whereas in the case of TV, all full power analog stations received a second channel for DTV broadcasting for 10 years (which has now turned into 12-1/2). There is also less of an incentive for radio to change to digital-- it won't necessarily free up valuable spectrum, as the DTV switchover did. Finally, DTV transmission offers consumers a clear improvement (at least in some ways) over analog, whereas HD radio does not (it does not offer better sound quality and it is not more robust).

If industry feels that it is necessary to switch to digital transmission, I favor the BMC proposal to open the channel 5 & 6 spectrum to digital-only transmission, but not with iBiquity technology. Whatever technology is selected should be "open source", and not require the payment of royalties indefinitely to a cartel. Otherwise, it will never be viable for small and medium market stations. There should also be a transition period of 5-10 years, with a "date certain" for analog broadcasting to cease. I'm not sure what we do with the AM band at that point, but the FM spectrum could allow additional "voices" to come on the air in the form of low power, community, event, and license-free broadcasting.

 

[stormy01]

If industry feels that it is necessary to switch to digital transmission, I favor the BMC proposal to open the channel 5 & 6 spectrum to digital-only transmission, but not with iBiquity technology. Whatever technology is selected should be "open source", and not require the payment of royalties indefinitely to a cartel. Otherwise, it will never be viable for small and medium market stations. There should also be a transition period of 5-10 years, with a "date certain" for analog broadcasting to cease. I'm not sure what we do with the AM band at that point, but the FM spectrum could allow additional "voices" to come on the air in the form of low power, community, event, and license-free broadcasting.

From what many of us have been saying about "HD" radio that would be a good solution... unfortunately, at this point it seems so unlikely. Even though digital radio has been tried primarily in Europe, it has been a dismal failure, and some countries as we know have already shut down or reduced their digital radio networks. "If it's not broken, don't try fixing it"

 

[RadeoEngineer]

Leonard has always been his own worst enemy.

 

[Carmine5]

Absolutely. Case in point is how he handled presenting CAM-D to the radio industry. When the FCC issued it's May 31, 2007 R&O regarding HD Radio it said this:

"112. In a petition for rulemaking filed January 24, 2003, Kahn Communications, Inc. requests
that the Commission initiate a new proceeding to revise procedures for evaluating new technology. Kahn
also requests that the Commission stay theDAB R&Oand reevaluate its adoption of IBOC in light of any
resulting policy revisions. To the extent that Kahn’s filing is a petition for reconsideration of the DAB
R&O,the petition is untimely. Kahn provides no justification for failing to file timely comments in this
proceeding. Moreover, we do not find that the public interest would be served by further delay of the
long-contemplated digital conversion of the terrestrial radio service. Therefore, we will not consider
Kahn’s untimely comments in this proceeding."

So Lenny missed a filing deadline. And, as I understand it, during the DAB evaluation phase he was invited on several occasions to demonstrate CAM-D and failed to do so. So the blame for CAM-D's failure totally rests at Mr. Kahn's feet.

C5

 

[Play Freebird]

The digital modulation technology used in Kahn's CAM-D system is apparently covered by US Patent 4,688,255, awarded in 1987:

http://www.google.com/patents?id=RCk7AAAAEBAJ&printsec=abstract&zoom=4&dq=4688255

As I understand it, he uses the data transmission signal to regenerate the higher audio frequencies through some type of lossy codec, but below 7.5 kHz, it's pretty much the same as his analog AM stereo system. I've never heard a demonstration, so I wonder how phony it sounds in comparison to HD Radio's low bitrate SBR codec.

Note that if the BMC proposal is adopted, this (expired) patent could offer the means for AM stations to send "alternate frequency" data to receivers, so that they could automatically retune to the VHF digital simulcast. In the meantime, the system might allow callsign, title and artist data to be transmitted, along with a link to the station's web stream.

I consider Leonard Kahn much like Major Armstrong: a brilliant engineer -- but no match for the American corporate legal system, which thrives by cheating productive, creative people out of just compensation for their ideas.

 

[rbrucecarter5]

The key fact here is that this system still requires consumers to buy new radios.

Wrong! The Kahn system, and probably Cam-D - only requires two radios, one tuned slightly low, and the other slightly high - to produce a pretty good facsimile of stereo. I've done it on a Kahn station, it sounds really good.

What killed AM stereo was a combination of factors -

(1) wishy washy FCC that wouldn't choose a standard. They corrected that with IBOC. They acted quickly - rashly - and adopted a fundamentally flawed system

(2) The rise of talk radio on AM - which made stereo and good quality sound irrelevant. That hasn't changed in 30 years and won'f for the benefit of iBiquity.

(3) The migration to FM, which is mirrored today by the migration to iPods and streaming. Nothing will stem the tide. AM was dead when top-40 moved to FM. FM was dead when people decided they didn't like the limited playist, excessive commercials and they could put an iPod in the pocket with their own playlist, or stream what they want to hear at the office. Cars are the last streaming frontier - when that is breached, FM will be like AM, brokered ethnic, leased, talk, and sports. And somebody thinks HD-2's will fix THAT problem.

 

[TheBigA]

The key fact here is that this system still requires consumers to buy new radios.

Wrong! The Kahn system, and probably Cam-D - only requires two radios, one tuned slightly low, and the other slightly high - to produce a pretty good facsimile of stereo. I've done it on a Kahn station, it sounds really good.

I'm not talking about stereo. I'm talking about Cam-D. Here is a quote from the above link:

"At present, there are a limited amount of special receivers capable of receiving CAM-D. According to Leonard Kahn however, the system has seen potential growth within the past year (2007)[1]."

So as I said, it requires a "special receiver."

 

[Tom Wells]

I had long ago thought about building a 455khz IF amp with two output "cans", one to favor the upper sideband, the other to favor the lower sideband. maybe I'll get around to it someday. It should work OK. If there's an easy way to do the same on transmit for my Part 15 AM, I haven't thought of it yet, but I have some complicated ideas on how to do it with high-q tuning output networks.