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AM HD - Ibiquity throws in the towel

Some interesting words in the latest Ibiquity pat-us-on-the-back press release

>>The future for AM HD Radio doesn't feel nearly as secure. Ibiquity seems to have made a concession to the reality of staying alive here and now on the medium-wave band by offering a compromise mode of AM IBOC that trades down digital bandwidth for acceptable analog audio quality. Among AM license holders, interest these days seems to have shifted from a digital solution to AM's woes to what's available in the next FM translator filing window.<<

http://hdradio.com/the_buzz.php?thebuzz=419

And we've only said this since, what, 2004?
 
"Acceptable"? Better than the days of the old, old flamethrowers, but it still transforms any 50kw AM using it into the audio
equivalent of a 250-watt county-seat daytimer two counties over on a winter day back in the 70's.
Kinda clear, but no escape from the background of hiss.
When their mode can tolerate full, normal AM modulation, not some crippled -94% max neg modulation, I'll be impressed.
ANY dumbing-down of the analog to "allow" the digital to work is still not acceptable.

I wish they'd throw in this particular towel. It's 100% polyester and absorbs no water at all.
 
wgliradio said:
Some interesting words in the latest Ibiquity pat-us-on-the-back press release

>>The future for AM HD Radio doesn't feel nearly as secure. Ibiquity seems to have made a concession to the reality of staying alive here and now on the medium-wave band by offering a compromise mode of AM IBOC that trades down digital bandwidth for acceptable analog audio quality. Among AM license holders, interest these days seems to have shifted from a digital solution to AM's woes to what's available in the next FM translator filing window.<<

http://hdradio.com/the_buzz.php?thebuzz=419

And we've only said this since, what, 2004?

Maybe even earlier. All along, we "naysayers" have pointed out that IBOC offers no solution to the far more significant problem faced by small, local AM broadcasters, which is inconsistency between day and night coverage. For those AM licensees who were fortunate enough to acquire the necessary licenses and move them to more effective sites before the FCC imposed a slowdown in application processing, FM translators have made a big difference -- in some cases, the difference between life and death.

Our new concern is that those FM signals remain free of interference from increased-power FM IBOC operation.
 
Yes: because there is NO "digital solution to AM's woes," at least not in the world of reality where most of us broadcasters live. RDM isn't gonna happen and HD-AM doesn't work. "So that's the name of THAT tune."

I'd be tempted to wonder aloud: what's next, the Commission turning over licensing of FM translators for AM stations to iBiquity - kind of like how they shoved ham licensing off on the ARRL?

But then I remember that the twelve remaining employees at iBiquity might find the workload imposed by such outsourcing, somewhat daunting.... :D
 
All is not lost... I hear Vladimir Putin has expressed interest in buying AM IBOC exciters for use as jammers on the shortwave bands. :D
 
I agree. "Baghdad Bob" Struble will still be obstinately insisting that HD-AM has a bright and sparkling future when the pop-count of operating HD-AMs has dwindled to ten.

(We're headed that way....Barry McLarnon, late contributor to RW, notes on his site that two more AMs have thrown in the Digital Towel, bringing the total of operating HD-AMs to 253, a new low down from a 2008 total of almost 290.) www.topazdesigns.com/iboc/station-list.html

That being said - "radio magonline," and its print predecessor Radio Magazine, are house organs completely produced by Broadcast Electronics. BE is a fine company - two of our four transmitters are BE units - but they're hardly a detached and objective observer of IBOC. They have a huge financial stake in selling HD equipment so the positive editorial stance is as obvious as it is understandable.

Actually, given BE's circumstances I find the candid comment about IBOC on AM to be somewhat remarkable.
 
I hasten to correct my earlier post. A good friend and associate in the broadcast industry - I don't want to name-drop, but suffice it to say his initials are "Scott Fybush" - has pointed out to me via e-mail that in fact, radiomagonline and its predecessor Radio Magazine are in fact published by Penton Media of Kansas City, goin' to Kansas City yes I am, and not by Broadcast Electronics.

We regrets duh error. :p
 
Penton Publishing? Pretty dang sure I've worked on their presses about 5 years ago.
Not suprised that Penton does (or did) Radio Magaizine. but I am that if they did, I didn't notice that.
I allmost always borrowed reception area display magazines to read at the hotel and retrun the next day.
I would have seen Radio Magazine on a showcase fan-out display.
 
>>Ibiquity seems to have made a concession to the reality of staying alive here and now on the medium-wave band by offering a compromise mode of AM IBOC that trades down digital bandwidth for acceptable analog audio quality. <<
Does this mean analog audio quality w/IBOC was unacceptable before? ???
 
A 5KHz brickwall filter makes analog sound like cr*p; "give me 10.2KHz or give me death", says Patrick Analog Henry. Take a listen to WNMB, 900KHz in North Myrtle Beach on a decent AM stereo car radio (like is in every one of the last vintage of T-Birds made) and you'll be blown away by the stereo audio quality.
Same for WJR BEFORE they installed HD - they has the world's sweetest analog audio on Earth, especially when they ran music programs on the weekends, and when they had the home Detroit Tigers games in stereo! Analog done right is great.
Now just give every 3-letter 1A station (WGN, WLS, WJR, KJR, etc) 750KW, and then we're talking something to overcome all the switching power supply BS these days!
 
ajc_trw mused:
"Does this mean analog audio quality w/IBOC was unacceptable before?"

If you are in the Portland area, listen to KEX sometime. On analouge MW, not IBAC. You can find KEX between 1180 and 1200. Of course, being that the majority of KEX's programming is right-wing political talk, its audio quality is inherently crap (with or without IBAC.) But don't let that fact throw you......
 
JohnnyElectron said:
A 5KHz brickwall filter makes analog sound like cr*p; "give me 10.2KHz or give me death", says Patrick Analog Henry. Take a listen to WNMB, 900KHz in North Myrtle Beach on a decent AM stereo car radio (like is in every one of the last vintage of T-Birds made) and you'll be blown away by the stereo audio quality.
Same for WJR BEFORE they installed HD - they has the world's sweetest analog audio on Earth, especially when they ran music programs on the weekends, and when they had the home Detroit Tigers games in stereo! Analog done right is great.
Now just give every 3-letter 1A station (WGN, WLS, WJR, KJR, etc) 750KW, and then we're talking something to overcome all the switching power supply BS these days!
If the trends continue, the AM frequencies will be opening up all over the place, that 750KW, would make WSM a nice sounding station down here. I can see the cleaning up of the band - and soon.

The only question is, if the CFO's will think that the electric bill is too high for ROI.

Jeff in Sa-ra-so-ta!
 
Since WLW's diamond tower took 500KW (without too many problems that engineers of the day couldn't fix - like their 100% modulation lock-up breaker and super johnnyballs), I wonder if they could pump 750KW out of WSM's diamond? That would be a good use of electricity, especially if 660 turned-off their "digital crop-duster" on WSM's signal here in Ohio. An AM station with decent programming - now that's a rarity (like WSM).
 
See, the problem is that this guy wants everybody to raise their power. He claims this will not make any difference in the interference level, but I believe it will. Remember what happened when all the Class IV locals raised their nighttime power from 250 to 1K? Same deal, only more so.

This is definitely one of the dumbest ideas ever, and the electrical power wasted would be horrendous. You would not be able to hear any better than you do now, except inside of a downtown building. Other than that, these stations would just kill each other off.

Ever heard the 50 kW carriers on 1530 grinding against one another? Imagine that at 500 kW apiece!
 
audioguy said:
See, the problem is that this guy wants everybody to raise their power. He claims this will not make any difference in the interference level, but I believe it will.

Well I think we're all assuming the weak pea shooters will go away. One they go away, the world will be run by the big canons.
 
According to the accounts I've read, the problems with 500kw at WLW weren't related to the 900' Blaw-Knox diamond. The major problem was with the 500kw "linear" added by RCA-Westinghouse-GE to the original 1927 water-cooled 50kw Western Electric, which then served as an "exciter" for the big rig.

Inadequate power supply regulation reportedly caused chronic HV flashovers on modulation peaks. Engineers on WLW's staff reported that notwithstanding the immense carrier power, the 500kw rig really couldn't modulate very densely. Of course this was in the era predating automatic gain control; most of the "limiting" was done by a human being with a hand on an audio fader (not very fast attack time.) One wonders if the WLW Big Rig would have thrown out a better signal if it had an Omnia in the audio line! :D

Supposedly the 500kw rig underwent a redesign in the 1950s as the FCC reconsidered superpower for AM, and the Avco engineers felt with appropriate modification WLW could actually get as much as 750kw out of it.
 
Savage said:
Supposedly the 500kw rig underwent a redesign in the 1950s as the FCC reconsidered superpower for AM, and the Avco engineers felt with appropriate modification WLW could actually get as much as 750kw out of it.
At the beginning of the Cuban Missile Crisis, WLW filed an application to operate at 750 kW. The application was mysteriously denied the day the Crisis was over. It is known and documented that the government used WLW to transmit Spanish language propaganda to Cuba during the Crisis, but you can guess for yourself whether or not they operated at anything above 50 kW.

FCC database for WLW said:
10/17/62 Application made for a C.P. for 700kc, 750kw, unlimited, and to make changes in transmitter. Request waiver of Section 3.21(a)(1) and 1.354 of Rules. Denied 11/21/62.
 
I noticed that WTEM 980 in DC has turned off its IBOC recently and I don't see the station in the Ibiquity website's DC station list anymore. I wonder if the hissing is gone for good?
 
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