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Has HD got stronger?

J

jras20

I noticed one of the stations now in Austin I can recieve in HD with my antenna going to San antonio use to I cant, I also noticed fewer drops than I use to have they increased the power? It seems like it.
P.S. KKMJs signal is still not strong... but I can get KFMK's HD signal great now.
 
HD is so new that stations are still tweaking it quite a bit. Reception will get better as engineers and radio manufacturers learn more about how to design for this technology. It's like radio in 1930...four or five years after the first commercial broadcasts, tv in 1950, or the World Wide Web in 1995. It WILL get better.
 
jras20 said:
I noticed one of the stations now in Austin I can recieve in HD with my antenna going to San antonio use to I cant, I also noticed fewer drops than I use to have they increased the power? It seems like it.
P.S. KKMJs signal is still not strong... but I can get KFMK's HD signal great now.
Click to expand...

More IBUZZ/IBLOCK - can anyone say, "Catch - 22" ? :D
 
PocketRadio said:
jras20 said:
I noticed one of the stations now in Austin I can recieve in HD with my antenna going to San antonio use to I cant, I also noticed fewer drops than I use to have they increased the power? It seems like it.
P.S. KKMJs signal is still not strong... but I can get KFMK's HD signal great now.
Click to expand...

More IBUZZ/IBLOCK - can anyone say, "Catch - 22" ? :D
Click to expand...

What do you mean by buzz? I dont understand, I dont hear that in my analog radios it does not effect any of the stations I dx to either on analog.
 
Neither does anyone else hear "buzz" on FM. I have many times challenged those who claim that they do to post recordings proving it. The world waits!
 
jras20 said:
PocketRadio said:
jras20 said:
I noticed one of the stations now in Austin I can recieve in HD with my antenna going to San antonio use to I cant, I also noticed fewer drops than I use to have they increased the power? It seems like it.
P.S. KKMJs signal is still not strong... but I can get KFMK's HD signal great now.
Click to expand...

More IBUZZ/IBLOCK - can anyone say, "Catch - 22" ? :D
Click to expand...

What do you mean by buzz? I dont understand, I dont hear that in my analog radios it does not effect any of the stations I dx to either on analog.
Click to expand...

Every day, I hear WTWP 1500 AM-HD buzzing all over WTRI 1520 AM, even in their protected contour.
 
The discussion was about FM STATIONS! There is no FM BUZZ! I've actually heard recordings of buzzon AM, and they concern me (although I have yet to experience this interference myself...there just aren't any HD AM stations around here yet).

But as for FM, North Carolina has PLENTY of those, and THEY ARE NOT causing a "buzz" or any other kind of interference.

Stick with the topic...FM is a different kettle of fish from AM. FM WORKS, and works well. Period! Listen for yourself. This is a recording from 80 miles away, using an indoor antenna, and the most inexpensive HD radio offered to date (until the new Radiosophy ceases to be vaporware)...the Accurian. The actual recording was 2 1/2 hours. Not a single dropout...just VERY high quality audio. And this is a station that multicasts...the file is their HD2 stream. No sane person can say this doesn't sound better than analog fm stereo from 80 miles away!

http://www.theproductionroom.net/shuffle.wma
 
jras20 was using an FM-HD station as an example, and I used an AM-HD station - the title of the thread had nothing to do with FM-HD, in particular. If IBUZZ is increased across-the-board, then the situation will be worse on AM.
 
Mike Walker said:
The discussion was about FM STATIONS! There is no FM BUZZ! I've actually heard recordings of buzzon AM, and they concern me (although I have yet to experience this interference myself...there just aren't any HD AM stations around here yet).

But as for FM, North Carolina has PLENTY of those, and THEY ARE NOT causing a "buzz" or any other kind of interference.
Click to expand...

On FM, the first-adjacent channel interference sounds more like a "whine" than a buzz. I can definitely hear it "fighting" with weaker analog signals that are first adjacent to local HD stations, once I reach the 60 dBu contour of the source of interference. Closer in, it just resembles white noise and completely masks the distant signals.

Mike, I'm sure your experience with HD has been positive, considering that you live in NC where most FM stations are Class C facilities, transmitting 100 kW from tall towers. Every time I drive down south, I'm impressed with that solid coverage.

But here in the northeast corridor, power limits are lower -- for example, a Class B station with antenna 1000 ft above average terrain would only be allowed 12.5 kW -- not to mention, we have many short-spaced first adjacent pairs. Many of the Philadelphia stations have a neighbor in New York about 80 miles away, whereas the normal separation requirement is 105 miles. There are similar short-spacings in most other densely populated regions of the US.

Overall, I've found the FM HD system works better than I expected, but there are many spots in this area (within predicted 60 dBu contours) where it drops out. Options to improve the system's performance are limited until a conversion from hybrid to "full digital" operation takes place, but this isn't realistic until automobile HD receiver penetration increases WAY above the current level. And GM, Ford, Toyota, etc. still don't offer factory-installed HD! Consider that the average age of vehicles on the road today is about ten years and I think you'll understand the problem. I doubt we will be able to drop hybrid operation until at least 2025... but, will consumers tolerate coverage problems that long?
 
Obviously there's room for improvement. We DO have lots of big-signal FMs in NC, but certainly not "every station".

Could you please post a recording of what "HD Whine" sounds like? I'm not being facetious, I've actually NEVER heard ANY interference on FM from HD.
 
Play Freebird said:
I doubt we will be able to drop hybrid operation until at least 2025... but, will consumers tolerate coverage problems that long?
Click to expand...

No doubt, HD/IBOC will have destoyed the AM band, before 2025 - listeners will be driven away in droves. There are an estimated 800 million analog radios/devices in the US, and an estimated 80 million analog radios/devices continue to be sold every year. Bridge Ratings continues to down-grade their estimate of the number of HD radios sold by 2010, from 12 million to 2.5 million - this figure is still way too high. iBiquity has admitted to having sold only 150,000 HD radios so far (not counting the number returned), so we can assume that their figure is over-stated, anyway. That leaves 18 years for HD Radio to replace the 800 million analog radios, and undermine the sale of 80 million analog radios every year. There are serious issues with in-dash HD Radio and HD Radio can forget about getting chipsets into cell phone type devices. The curve for consumer interest in HD Radio has been almost flat for the past 3 1/2 years, except for interest from the radio-geeks. The FCC has left the fate of HD Radio up to the marketplace - I'de say, that the outcome is not too hard to figure out.
 
I've never heard any extra noise on any of my fine analog FM stereo tuners since stations began broadcasting in digital. AM, on the other hand, has increased noise in analog on stations that use HD. However, said AM stations do sound excellent in digital, so it is a worthwhile tradeoff. 8)
 
Mike Walker said:
Obviously there's room for improvement. We DO have lots of big-signal FMs in NC, but certainly not "every station".

Could you please post a recording of what "HD Whine" sounds like? I'm not being facetious, I've actually NEVER heard ANY interference on FM from HD.
Click to expand...

This shoudn't be too hard. The buzz I can record easily. The trick will be whether I can find one of the "stations between the stations"
where the audio is still somewhat audible, but ibuzzed.. most of them are just ....gone.
And there never were too many of them for me, as the Chicago FM dial is FULL.

scanman1 said:
I've never heard any extra noise on any of my fine analog FM stereo tuners since stations began broadcasting in digital. AM, on the other hand, has increased noise in analog on stations that use HD. However, said AM stations do sound excellent in digital, so it is a worthwhile tradeoff. 8)
Click to expand...

Wow! I'd much rather hear the old analog interference on AM than the garbled echoey HD . All speakers on AM HD sound like they need to clear their throat really badly.
 
If you are talking about that slight buzz in between the channel adjustment, that does not effect me at all. Infact, I can get analog signals more better from that, for example, I can pick up KKMJ, which does have a HD-2 side channel, and DX to KLEY south San antonio just fine. If someone knows of a free file host I can upload a clip of a small buzz...
 
FM stereo is fine when a station broadcasts IBOC. There is nothing you can tell that a station is in digital whenyou listen to it. However , if you listen lets to a station at 92.5 FM and you drive into its fringe coverage area and the station next to it 92.3FM does IBOC , you will do loss the distant station sooner from IBOC interference. Also tune to a strong local with IBOC, then tune either +/- 200KhZ , you will hear the IBOC hash on the open channel.
 
mgpt6 said:
FM stereo is fine when a station broadcasts IBOC. There is nothing you can tell that a station is in digital whenyou listen to it. However , if you listen lets to a station at 92.5 FM and you drive into its fringe coverage area and the station next to it 92.3FM does IBOC , you will do loss the distant station sooner from IBOC interference. Also tune to a strong local with IBOC, then tune either +/- 200KhZ , you will hear the IBOC hash on the open channel.
Click to expand...
Other than first adjacents there are no open channels in the NY metro area.
 
Mike Walker said:
Obviously there's room for improvement. We DO have lots of big-signal FMs in NC, but certainly not "every station".

Could you please post a recording of what "HD Whine" sounds like? I'm not being facetious, I've actually NEVER heard ANY interference on FM from HD.
Click to expand...
Mike,
I am a fan of HD FM, but I have to admit that there is a slight degree of interference that only DXers would notice. I will cite a local example here in the Cincinnati area. There is a local in Cincinnati on 102.7(WEBN). Prior to WEBN running IBOC, a station on 102.9 was receivable from Springfield which is about 70 miles distant. Now when you tune to 102.9, a hiss is heard which resembles the white noise heard on an empty FM channel. Apparently the digital signal was designed to sound like the white noise. In a nutshell, when you tune to the first ajacient of a local FM that is running IBOC, what sounds like the white noise of an empty channel is actually the digital signal. The digital hash is there but is well hidden.
 
I've tried encoding the audio from first-adjacent interference and it just sounds to subtle to hear after encoding. But, it's very much present. I could ask the same of someone with an analog VCR, to record interference from a DTV station. The interference looks very much like vacant-channel "snow", but there is indeed a difference, and it indeed blocks analog reception, even though it can't be recorded on analog equipment.

The interference is there. It's nowhere near as horrid (and clearly obvious) as HD AM, but it exists. First-adjacents have louder background hiss than frequencies two channels (0.4 MHz) away from HD stations. I am not making this up, and I am obviously not the only person who is capable of hearing this. I've said this before (but certain people blatently ignore this) that I was easily able to tell which Chicago stations were running HD Radio long before I owned an HD Radio. It's the modem-like hash, buried underneath what sounds like amplified thermal noise. One other poster out here described it dead on.

In the car, attempting to listen to a first-adjacent covered by HD Radio hash gives a really strange effect. The analog station rapidly fluctuates from clearly audible, full-quieting, and in stereo to complete hiss. It's as if someone is opening and closing a microphone over the audio while blowing into it.
 
Mike, I respect your opinion, but I hear it too. I posted my description of what it sounds like a few weeks ago. I'm not hearing things, but I just don't have time to drive to Dallas and record this for you. I’m not in the service area of any HD station.

As a previous post said, it does sound "almost" like white noise. It is closer to Pink Noise, which has more low frequency content. On top of that, there is a strange swirling sound in the background at a very low level. The noise is unlike anything you will hear on the adjacent channel of any analog only station. Whether or not this sideband is significant or not remains to be seen. In most cases, I'll bet that it is not a real problem. For closely spaced stations, especially those in the Reserved Band in the Northeast, I'll bet that it is a problem.
 
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