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KRKO/KKXA To Test All Digital AM Broadcasting

I heard a rumor that HD radio was never intended to improve the AM dial. Rather, iBiquity only developed the AM technology to fulfill some sort of requirement. I'm curious to find out if it could be true.

As I recall, digital IBOC was originally intended for AM only. FM came along later. AT&T was the main leader in the modulation scheme for AM, later merged into Ibquity. If you've ever had the chance to listen to the AM-HD broadcast, it sounds pretty good, similar quality to an FM station. Here on the East Coast during the fall and winter months, I regularly listen to WLW-HD from Cincinnati and WCBS-HD in NYC while driving home in Central Virginia. The sound is much more pleasant and easy to listen in digital mode.
 
And you don't hear that pesky pattern change in the morning and in the evening. That was one of the coolest things I noticed.

Looking into my crystal IBOC ball. I see a Nautel engineer updating the firmware on both the KRKO and KKXA XR50 transmitters to go into MA3 mode as it's called. No testing tonight (Thursday night). They may flip both into all digital/MA3 mode to test the firmware but this is not the beginning of their official test. That actually starts on Friday with daytime Hybrid mode/MA1, which is the normal hybrid mode IBOC stations use now to have the analog and digital carriers.

The actual all digital will happen at 9pm Friday till 1am Saturday morning on KKXA.
KRKO, day test's Saturday 9:30am till 4:30pm
KKXA, night test's Saturday 9pm till 1am Sunday morning
KKXA, day test's Sunday 9:30am till 4:30pm
KRKO, night Sunday 9pm till 1am Monday morning
KRKO, night Monday 9pm till 1am Tuesday morning

So it looks like both stations will not be digital at the same time, unless they test that tonight after midnight to see how that looks into the antenna system, which I bet they do. So at least one station will be listenable for regular AM radio's during the test's which start Friday night. Andy has assembled a team of engineers and has rented several cars with HD radio's to do the listening. I see some fun road trips in their future.
 
As I recall, digital IBOC was originally intended for AM only. FM came along later. AT&T was the main leader in the modulation scheme for AM, later merged into Ibquity. If you've ever had the chance to listen to the AM-HD broadcast, it sounds pretty good, similar quality to an FM station. Here on the East Coast during the fall and winter months, I regularly listen to WLW-HD from Cincinnati and WCBS-HD in NYC while driving home in Central Virginia. The sound is much more pleasant and easy to listen in digital mode.

So you pick up the HD carrier of the skywave? I'm under the impression that the signal is non existent after leaving the contour (like with FM HD).
 
Friday night. Andy has assembled a team of engineers and has rented several cars with HD radio's to do the listening. I see some fun road trips in their future.

Now there is a fun job! :) If any of you guys are planning to test out the signals with your car mounted HD radios, please post your results.
 
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So you pick up the HD carrier of the skywave? I'm under the impression that the signal is non existent after leaving the contour (like with FM HD).

Skywave is skywave...the emission mode doesnt matter......as long as the receiver can decode it properly....
HD on AM has lost a lot of backing from the big groups....I dont see all digital happening due to the lack of receivers...GM has taken HD out of a lot of models (yet put it in new models this year) because they did not feel comfortable with the switching taking the drivers concentration from the road..
 
Skywave is skywave...the emission mode doesnt matter......as long as the receiver can decode it properly....
HD on AM has lost a lot of backing from the big groups....I dont see all digital happening due to the lack of receivers...GM has taken HD out of a lot of models (yet put it in new models this year) because they did not feel comfortable with the switching taking the drivers concentration from the road..

Yeah, I have heard a lot of backlash over the HD receivers mounted in cars. Countless vehicle owners are demanding a way to turn off the HD system.
 
I've heard that digital does work with skywave, but there can't be any interference or the signal has to be above a certain threshold...some have posted in this very forum in the past that they've received skywave hd. The biggest problem was that the digital signal only uses 1 tenth of the power when in hybrid mode, so at such low power levels, the signal doesn't go very far. An all digital signal at 50kw will get out quite well, and the tests on WBT worked really well.
 
I've heard that digital does work with skywave, but there can't be any interference or the signal has to be above a certain threshold...some have posted in this very forum in the past that they've received skywave hd. The biggest problem was that the digital signal only uses 1 tenth of the power when in hybrid mode, so at such low power levels, the signal doesn't go very far. An all digital signal at 50kw will get out quite well, and the tests on WBT worked really well.
It is possible with HD, but I am under the impression that it is difficult to pick up a tropospheric signal, and or borderline impossible to receive an e-skip. The distant radio signals that I enjoy are all right in the "sweet spot" where the signal is very well listenable on a good day, with minor, intermediate interference. I think its safe to assume that there would be no signal at all if the signal were exclusively HD. I can certainly live without listening to my out of town signals, but we don't live in a world where the population of a given area is centred around a metropolitan area. For the folks who are far off... best of luck.

I've got a DTV converter box that will show me the percentage of signal making it into the box. There is most definitely a cliff effect where you get perfect coverage above a certain percentage, and nothing below that percentage.
https://www.youtube.com/watch?v=m6LdH7Iwulg
 
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They've changed their web page, with the KRKO details staying the same:
Saturday 9:30 AM-4:30 PM
Sunday and Monday nights: 9 PM-1 AM

The KKXA test times are different (and they _did_ say subject to change till October 2!)
KKXA test listed now as:
Saturday night 9 PM-1 AM
Sunday 9:30 AM-4:30 PM
Tuesday, October 7: 9 PM-1 AM

I know, I know; everything I originally read specifies that the tests are between October 2 and 6.
I'm finding these listings at:
http://www.everettpost.com/pages/11648427.php
 
As I recall, digital IBOC was originally intended for AM only. FM came along later. AT&T was the main leader in the modulation scheme for AM, later merged into Ibquity. If you've ever had the chance to listen to the AM-HD broadcast, it sounds pretty good, similar quality to an FM station. Here on the East Coast during the fall and winter months, I regularly listen to WLW-HD from Cincinnati and WCBS-HD in NYC while driving home in Central Virginia. The sound is much more pleasant and easy to listen in digital mode.
AM was an afterthought. The NTIA and CBS Labs developed a system and eventually merged with other competing systems, taking the best elements from each to form Ibiquity. I don't ever recall hearing anything about AT&T being involved in the process.
 
Back in 1990 I remember seeing a demo given at NAB from AT&T of their AM IBOC solution which as I understand it, evolved into the Ibquity model used today (sort of).
 
One thing I disagree with Kelly on (and it's a personal taste thing):
I don't like the sound of most AM IBOC I've heard. Low bit rate, artificial-sounding.
But then again, some people don't find anything annoying about listening to a 32K mp3 stream, and I can't stand to listen to one.
I'm especially eager to see if a higher-bit-rate stream on AM is more pleasant, as I'd expect it to be.
Even if this test is fantastic, I can't imagine an orderly process to convert the whole AM band and persuade millions of people to give up their current equipment while stations give up their guaranteed listener base in hopes of getting an expanded one, especially since AM programming is often less than inspiring to begin with.
But I salute Andy for doing this, and while I'm about as anti-IBOC as anyone can be, I'm glad for the chance to hear the results for myself.
 
After Conservative Talk dies completely, it will be more like "thousands of people"!

That's actually an interesting point. (Aside from the comment about conservative talk, which I have no comment.) In order to rebuild AM listening with the next generation, does the AM band 'building' need to be just torn down one station at a time to start fresh? I'm not saying I have an opinion one way or the other, mainly because there are valid arguments on both sides. It would to take a station owner or group who is forward thinking and willing to sacrifice their existing analog audience on an AM station to move the process forward. Evolution or extinction.
 
To make AM at all marketable for the next generation, they need to make it easier. I don't see any young individual spending the money to get HD equipment to hear the bogus programming on 1090 or 850. However, it could take off with a few changes.

Having said that, our class A, 50KW signals have plenty of life in them for the extended future. People are always want news and sports radio, and you could also stick popular formats on some of these signals as well (if they ever engineer it to work and sound like FM).

It would be a good oasis for such formats as
KIRO 710 - All 2010's 'Bro Country' all the time!
KOMO 1000 - The Nicki Minaj and Iggy Azealia connection.
 
Every one complains there is no Local programing. Maybe a fan of Thunderbirds Hockey would listen to KFNQ in HD. That is not Bogus programming. Last night they had Oregon and Arizona College football on. KFNQ has live sports. Just because your not into sports does not make the format Bogus. I enjoy the National take on the Seahawks or Mariners which KFNQ supplies, then I cam flip to 710 ESPN and get the local take.

With the right audio processing you can process the HD and analog differently and get good results from HD (Love Optimod 9400). Yes I listen to KFNQ mostly Analog but can sample the HD side also. Tyr this, listen to the Seahawks on KIRO 710 then turning to the broadcast on KIRO FM it's almost the same experience as switching form analog AM to the HD signal. In that aspect yes the HD signal sounds more like FM. AM and FM processing styles are different and so are the AM and HD processing. A good HD station will process the HD differently. Even the FM and FM-HD processing should be separate after the AGC to do a good job. I saw a thread where the topic was if a station is going to do HD it should be done right.
 
I've said it before, but I will say it again: There are many other things that some of the Seattle sports stations could cover that do NOT revolve around college football or basketball. Sure, it has a following, but a lot of things get ignored (NHL for example, but that is my personal taste). Overall, the programming on KFNQ does not need to be localized, but it could be nice to see some different programming.

1090 could be a pretty nice sports outlet, but its really not living up to its potential, and the lack of a website tells me that its more or less being used to store the frequency. I don't often tune into 710, but I can say that they really made KIRO "the place" to listen for anything going on in the Seattle sports world.
 
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Actually in honor of a station owner getting 3 or 4 rental cars, an NAB representative, a transmitter representative and their respective credit cards together with several broadcast engineers for a road trip. I'm celebrating with Tequila shots at 9pm tonight.

Watch for it....Broadcast engineers gone wild, road trip edition. I'm sure there will be a designated driver and hopefully Andy got the extra insurance coverage and unlimited millage.

I too am hoping some info comes out of this. What's the IP and EP on the transmitter when in MA3 digital mode. It would be fun to examine the expense reports for the NAB and Nautel participants. Was there any food trade involved? Oh to be a fly on the wall at that restaurant. How many coffee/expresso stops. Who stopped for the best lunch on the day tests. Maybe Andy will share.

And lets not forget the person that rents the rental cars after Engineers Gone wild, Road edition. Hopefully they clean them after each rental.

Cheers to Andy and the crew for this test. I raise a glass at 9pm (listening to my G8).
 
Looking forward to this all-digital test (and wishing it were KING-FM as well). However, my AM reception down here in Auburn using a Sony XDR-F1HD tuner and Terk Advantage tunable loop antenna isn't promising. I can _sometimes_ get a HD lock on an AM sports station in Seattle but not at all on KRKO or KKXA. In fact, KKXA doesn't come in at all when it goes directional at night, so I'm not optimistic.

Guess I need to start researching better AM antennas, maybe a long wire on my roof.
 
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