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Article mentioning AM HD

earshot

earshot

In today's Dan Mason tells RAIN Summit "I have a clearer understanding of where radio fits" article, this quote was included:

The CBS president also comes out strongly in favor of HD Radio, both AM and FM, and says "once digital takes over on AM, it completely cleans up the AM band." He acknowledges the need to get more HD Radios into the marketplace.


In regards to AM, that's not what I've been reading in these threads at all. I'm curious to hear from engineers the scientific views. Would it clean up the AM band? Or would it contribute noise to the band, as is mentioned here. Does he mean if every station on the band went HD, the band would be cleaned up (as opposed to digital and analog living side-by-side)?

In theory it sounds great but from people living in markets with AM HD, that doesn't seem to be the case.

Link to the full article:
http://www.radio-info.com/news/dan-...have-a-clearer-understanding-of-where-radio-f
 
If every station picked up hybrid digital operations it would devastate the band with side channel noise. If it were a clean break to 100% digital it would probably be slightly less relevant, but the issue of skywave interference would remain.

Digital and AM simply were not meant to go together, at least not in the form that's being foisted on us now. It's just not sufficient for high fidelity sound reproduction. Which is odd, considering wideband AM stereo is plenty sufficient for 75% of music and speech use NOW, but it's forgotten technology.
 
The big boys would love to own the AM band, and drive off all those small-time operators - especially after dark. If you've got 50KW, you'd love to go back to the days when everybody else on the channel went off at sunset instead of running their 100W to service their little local market.

HD - on either AM or FM - was never designed to be a friend to small players.
 
earshot said:
In today's Dan Mason tells RAIN Summit "I have a clearer understanding of where radio fits" article, this quote was included:

The CBS president also comes out strongly in favor of HD Radio, both AM and FM, and says "once digital takes over on AM, it completely cleans up the AM band." He acknowledges the need to get more HD Radios into the marketplace.
Click to expand...

I think that was a misquote he probably meant "completely clears out the AM band" :D
 
earshot said:
In today's Dan Mason tells RAIN Summit "I have a clearer understanding of where radio fits" article, this quote was included:

The CBS president also comes out strongly in favor of HD Radio, both AM and FM, and says "once digital takes over on AM, it completely cleans up the AM band." He acknowledges the need to get more HD Radios into the marketplace.


In regards to AM, that's not what I've been reading in these threads at all. I'm curious to hear from engineers the scientific views. Would it clean up the AM band? Or would it contribute noise to the band, as is mentioned here. Does he mean if every station on the band went HD, the band would be cleaned up (as opposed to digital and analog living side-by-side)?

In theory it sounds great but from people living in markets with AM HD, that doesn't seem to be the case.

Link to the full article:
http://www.radio-info.com/news/dan-...have-a-clearer-understanding-of-where-radio-f
Click to expand...

Clearly spoken by someone who does not understand relationships between "bandwidth" and "bandwidth".

At MW, .5- 1.7 Mhz, any digital transmissions are going to be challenged by the wavelength itself, and the
very poor definition of high speed data states relative to that 1-mhz-range carrier.

Oh, and he forgets to admit that there CAN be no digital signal unless an "analog" vestigal "carrier"
still exists to reference against. So the hash WILL be spread as wide as it is now, it just won't have to allow that
10khz of space for the 5 khz of audio to exist.

The digital sideband-products overlap in a totally-digital MW band would, I suppose, mean the AM band would become a daytimer.
Unless you happened to live in a VERY strong signal area.

Trying to decode WLS iboc from 40 miles away was pretty much impossible... I'm an engineer,
and I have kept this place pretty clean RF-wise.
 
Dan Mason apparently has no understanding whatsoever of principles of medium wave propagagtion.

Frankly, I don't respect his opinion on any aspect of broadcasting. Why not? Because I can't possibly respect an anti-labor executive who got his start in management as a strikebreaker.

See http://www.amandfmmorningside.com/wpgc_the_great_strike_that_struck_out.html

(And save it to a thumb drive, if not to your hard drive, before Mason finds a pay to get it pulled off the web!)
 
Anybody who thinks that HD "completely cleans up the AM band" is crazy. Or an idiot. Possibly both?

Tom Wells has cogently set forth the issue: not enough bandwidth. (Not to mention, not enough consumer or broadcaster interest. At its peak, HD-AM was broadcast on fewer than 2% of AM stations in the US and that since that time, early 2009, 21% of the few stations using the system have turned it off. I am unaware of any new AM-HD installations in over two years. Nor am I aware of any significant number of stations using AM-HD outside of the USA. There are no AM-HD receivers even being marketed any more, so far as I know. Precisely how are we "going to get more HD receivers into the marketplace" when they aren't even being sold?? How all these pesky little details escaped CBS Radio's CEO is anyone's guess, but I would suggest "willful blindness." Mason is a former top iBiquity executive, as is his engineer Glynn Walden, so they both probably have a financial stake in HD in the form of stock or paid consultancies or something.)

Even if there's some kind of nihilist-doomsday dream by HD perpetrators that somehow all smaller operators will be driven off the band leaving only big groups and, say, half the AMs that currently exist, HD still wouldn't work. The skywave interference from universal HD adoption would be catastrophic. Nobody would have any night service. And there would be no AM listeners left because (a) the digital signals aren't robust enough and (b) nobody's going to guy new AM receivers.
 
I'd love to see the day when AM goes completely digital. Hopefully they figure out a way to get rid of lightning or else you better be prepared for signal drops. And there wont be an analog signal to fall back on. Lightning storms are a fairly common occurrence during the summer, especially down south. We all know the lightning discharge sends crackles all over the AM band. While these are a inconvenience for people listening to analog, with digital the signal is lost and you have to wait for it to re-buffer.

Here are a few examples, and these people are listening within range of the station during the day.
http://www.youtube.com/watch?v=Ej31AftNYy8
http://www.youtube.com/watch?v=szd7lzGcyLU

We aren't talking about skywave here, although that brings its own problems such as adjacent channel noise. KDKA and WBZ is a great example. And how about WHAM turning off its IBOC at night while WWVA was on low power after its towers were destroyed. What about those low powered AM stations whose normal nighttime signal is weak, just like WWVA's was when they were running on temporary power. These stations get beat up all the time by IBOC making them un-listenable at night. WYSL 1040 in Rochester, NY saw a great amount of interference with their nighttime signal because of WBZ's IBOC signal traveling via skywave. The issue was never resolved, so WYSL settled for an FM translator.

I went into Best Buy recently and saw no mention of HD Radio. The selling points on all of the Radio/Entertainment consoles were iPod docking and internet connectivity for Pandora, etc. About the only place to find HD radios is online, and some great models like the SONY XDR-F1HD have been discontinued.
 
spunker88 said:
I went into Best Buy recently and saw no mention of HD Radio. The selling points on all of the Radio/Entertainment consoles were iPod docking and internet connectivity for Pandora, etc. About the only place to find HD radios is online, and some great models like the SONY XDR-F1HD have been discontinued.
Click to expand...

It's not being pushed but it's still there. The last store I went in still had a few Insignia portables, and one or two car units that were HD included (and several more just HD ready, blech.)
 
"[O]nce digital takes over on AM, it completely cleans up the AM band."
Click to expand...

"Once I finish smearing dog poo all over the floor, it completely cleans up the kitchen floor."
 
If I read the AM IBOC specs correctly AM HD in pure digital mode is 32 times higher in power, and the sidebands being moved in close to the broadcast frequency, mean the susceptibility of interference from 1st and 2nd adjacent AMs decreases. Regarding the lightning, the time diversity between the upper and lower sidebands, lowers the occurrence of dropouts compared to the less robust non-time diversity that quite a few AM HD stations employ. But yes if the lightning strike frequency above a certain threshold (multiple strikes throughout a 10 second window) will still knock it out, but the analog is not that great either a that point. Regarding skywave at night, asymetrical power levels of the sidebands could help mitigate the occurrence of co-channel interference, where station in certain in odd zones have strongest power on the upper sideband and stations in even zones have strongest power on the lower sideband. These zones could be, for example 500 km wide bands in whatever shape that would minimize skywave interference, e.g. 500 km wide concentric bands, vertrical bands, honeycombed shape (like the cellular industry). It goes without saying, that outside the primary coverage area it is likely that all the benefits of HD AM in pure digital mode would not be achieved during reception challenged conditions.
 
For what it's worth, HD is included in some new car radios. Our new MINI has AM & FM HD, and I was surprised to find that WHAM's HD signal decoded successfully at the dealership in Williamsville and didn't flip back to analog any more than 25% of the time in that vicinity. When we got closer to Rochester, I tried WXXI's FM HD-2 channel and was very disappointed with the frequent dropouts, which occurred even within sight of the antenna on Pinnacle Hill. As far as FM HD-1 is concerned, the audible difference between digital and analog is very slight, although some stations do transmit useful artist and title info which only shows up in HD mode.

After fiddling with the HD for a day or two, I gave up on it, especially since the MINI radio is plagued with very complicated menus and very small buttons. There is a menu selection that defeats the HD function entirely, although it's hard to find. I suppose FM HD-2 is fine for those "driveway moments" when the car is stationary and there's plenty of time to peer and poke at the radio.
 
If any member of the New York Assembly reads this thread and Lee's post, expect an anti-HD-in-your-Mini law to be passed, since they're crazed about anyone even holding a cellphone while driving. (Of course, they're ignoring people who dork with CDs and mp3 players, or gobble double-fatburgers and Big Gulps, or people putting on makeup or changing their shoes or smoking or reading newspapers and iPads or changing diapers or having domestic fights while driving.)
 
Lee Rust said:
For what it's worth, HD is included in some new car radios. Our new MINI has AM & FM HD, and I was surprised to find that WHAM's HD signal decoded successfully at the dealership in Williamsville and didn't flip back to analog any more than 25% of the time in that vicinity. When we got closer to Rochester, I tried WXXI's FM HD-2 channel and was very disappointed with the frequent dropouts, which occurred even within sight of the antenna on Pinnacle Hill. As far as FM HD-1 is concerned, the audible difference between digital and analog is very slight, although some stations do transmit useful artist and title info which only shows up in HD mode.

After fiddling with the HD for a day or two, I gave up on it, especially since the MINI radio is plagued with very complicated menus and very small buttons. There is a menu selection that defeats the HD function entirely, although it's hard to find. I suppose FM HD-2 is fine for those "driveway moments" when the car is stationary and there's plenty of time to peer and poke at the radio.
Click to expand...

"Driveway Moments" great theme for the inevitable new CBS radio HD push :D
 
Zach said:
... Which is odd, considering wideband AM stereo is plenty sufficient for 75% of music and speech use NOW, but it's forgotten technology.
Click to expand...
AM Stereo was not forgotten.

Just the opposite, it was crushed, killed, mutilated, and beatened down. Finally ridiculed.

A forgotten technology just goes away, such as 8-track tape and FMx.

Jeff in Sa-ra-so-ta!
 
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