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Author Topic: FCC approves all digital AM  (Read 4006 times)

Offline NJQA

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Offline ChrisSmolinski

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Re: FCC approves all digital AM
« Reply #1 on: November 23, 2019, 1327 UTC »
There goes the MW band. WWFD is semi local to me, and trashes both adjacent channels. Sigh.
Chris Smolinski
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Offline redhat

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Re: FCC approves all digital AM
« Reply #2 on: November 23, 2019, 1653 UTC »
the key language here is 'voluntary'.  There is no mandate to go to digital, and in my view for any station that would be suicide.  95% of the stations out there are running at low power, messed up arrays, bad audio, etc.  They don't have the money to fix what they have and no one is going to be forming a line at ibequity's door.  I think this is the last gasp of digital on AM here.

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Offline JimIO

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Re: FCC approves all digital AM
« Reply #3 on: November 23, 2019, 2039 UTC »
The local CC right wing AM talk station has a CP for an FM translator. I wonder if they are planning to go digital? That will surely confuse all their old listeners.    8)

~

Offline BoomboxDX

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Re: FCC approves all digital AM
« Reply #4 on: November 24, 2019, 1337 UTC »
Won't be much change to the band. Not many stations on the AM band use IBOC HD now. I don't see much change happening.

A handful of stations, in major metros, at best, may take the option.
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Offline pinto vortando

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Re: FCC approves all digital AM
« Reply #5 on: November 24, 2019, 2140 UTC »
I don't see much change happening.


good  :)
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Offline pinto vortando

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Re: FCC approves all digital AM
« Reply #6 on: November 24, 2019, 2142 UTC »
  I think this is the last gasp of digital on AM here.


let's hope   ;)
Das Radiobunker somewhere in Michigan

Offline Dude111

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FCC approves all digital AM
« Reply #7 on: November 25, 2019, 0805 UTC »
Quote from: redhat
the key language here is 'voluntary'.  There is no mandate to go to digital, and in my view for any station that would be suicide.

Yes but all the puppets will goto it anyway.. All the ones running IBOC will probably be the first.....


I wont listen to them if they do that so if they wanna lose listeners let them.....

Offline BoomboxDX

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Re: FCC approves all digital AM
« Reply #8 on: November 26, 2019, 0407 UTC »
Quote from: redhat
the key language here is 'voluntary'.  There is no mandate to go to digital, and in my view for any station that would be suicide.

Yes but all the puppets will goto it anyway.. All the ones running IBOC will probably be the first.....


I wont listen to them if they do that so if they wanna lose listeners let them.....

The ones who were running IBOC probably gave up on it for valid reasons, one of them being that the equipment finally broke down and/or wasn't cost effective.

If a local station happens to go all-digital I'll listen -- there are several stations that used IBOC in my metro, and they had decent formats (sports, South Asian, classic country, etc.). I'm not holding my breath for them to turn the digital on, though (see my previous sentence about equipment breakdown and cost effectiveness).
« Last Edit: November 26, 2019, 0410 UTC by BoomboxDX »
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Offline ChrisSmolinski

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Re: FCC approves all digital AM
« Reply #9 on: November 27, 2019, 1734 UTC »
I just realized, Digital AM (Amplitude Modulation) is an oxymoron.
Chris Smolinski
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Offline pinto vortando

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Re: FCC approves all digital AM
« Reply #10 on: November 27, 2019, 2040 UTC »
I just realized, Digital AM (Amplitude Modulation) is an oxymoron.

Well, not really, the present digital format is hybrid so it's both digital and AM.
Of course, pure digital is another matter.
Although IMHO none of it belongs on the AM band.
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Offline redhat

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Re: FCC approves all digital AM
« Reply #11 on: November 27, 2019, 2124 UTC »
Quote from: redhat
the key language here is 'voluntary'.  There is no mandate to go to digital, and in my view for any station that would be suicide.

Yes but all the puppets will goto it anyway.. All the ones running IBOC will probably be the first.....


I wont listen to them if they do that so if they wanna lose listeners let them.....

The major groups had to roll out a set number of station for the initial HD rollout, and as such were contractually bound for a period of time to keep them running.  Apparently the contract has run out.  The early HD stuff was not very reliable, using industrial PC's running custom OS to generate the HD waveforms.  The newer gear is a lot more reliable, but apparently no one wants to spend the money on something that nets them no return on their investment.  The only innovations making any headway in AM these days are those that save money or power, hence why MDCL is a thing now, particularly on the 50KW flame throwers where the power savings can be very noticeable.

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Offline Brian

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Re: FCC approves all digital AM
« Reply #12 on: November 28, 2019, 1013 UTC »
I just realized, Digital AM (Amplitude Modulation) is an oxymoron.

It's correct I think. It's the amplitude of the carrier that is modulated with digital information.

Offline NJQA

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Re: FCC approves all digital AM
« Reply #13 on: November 28, 2019, 1351 UTC »
I spent a little time this week listening to WWFD while driving around.  I am in the lower Southern edge of WWFD’s fringe area according to this:

https://radio-locator.com/cgi-bin/pat?call=WWFD&service=AM&h=D

My receiver was the factory radio in my 2017 pickup.

First of all, I was surprised at how well it worked.  I expected dropouts (and there were plenty) but they were far fewer than I expected.  As is normal with digital radio, everything was either perfect, or non existent.  When the signal was there, sound quality was markedly better than the normal AM radio I listen to.  In fact it sounded much better than our local 22kW station.

Looking at the spectrum on my SDR at home, I realized that this is a much better “neighbor” than stations running the hybrid analog/digital mode.  WWFD’s entire carrier is contained +/- 5 kHz of their assigned frequency.  The analog stations have their digital carriers on the adjacent channels.  Granted, their digital carriers are 30 dB below their carrier power, but they do interfere with stations on those adjacent channels.

So I have mixed feelings about this.  As a DXer, I abhor this as the digital carrier effectively wipes out a channel.  You can’t hear anything through this.  Last night I saw three strong hybrid stations that effectively wiped out the channels above and below them - and that was with them running the digital signal at -30 dBc.  A digital carrier will lock up a channel for DXing purposes.  You can’t hear anything thru it.  It is a white noise jammer.

But as a consumer, I would listen to digital AM radio for local listening. The sound quality is significantly better.  And whatever range problems the current hybrid system has will get much better if they can up the digital power by 30 dB!  WWFD was “listenable” in my fringe area-I imagine it is very usable where Chris lives.

This could gain steam.

The bright side is that if you replaced a local hybrid station with a pure digital station, you will probably get the adjacent channels back for DXing.
« Last Edit: November 28, 2019, 1356 UTC by NJQA »

Offline skeezix

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Re: FCC approves all digital AM
« Reply #14 on: November 29, 2019, 0215 UTC »
A bunch of years ago when WCCO transmitted IBOC hybrid, I tried it on a receiver at home. I'm 15 miles away and it sounded like a crappy Internet stream. AM sounded clearer & easier to listen to. The digital signal was annoying and had dropouts, even though they're a 50kW station and I was stationary a mere 15 miles away.

They have since turned off the hybrid and are on AM only. It sounds even better in AM now, since they're a bit wider in bandwidth and not that stupid 5 kHz audio (10 kHz RF) bandwidth which makes it sound muddled.

No locals on MW IBOC hybrid around here these days, so can't do any further tests. Do occasionally get the IBOC jamming from DX stations, but usually those are not stable enough for the receiver to lock onto for more than a few seconds.

As a listener, I found nothing useful with IBOC hybrid. It seems to be a solution in search of a problem.

If the problem is noise on the MW band, then the FCC can do something about that. RFI is bad these days- unintentional radiators from crappy electronics are all over the place. They not only radiate the signals, but also put it on the power lines which also distribute it over wide areas. Dirty power lines are very common here.


« Last Edit: November 29, 2019, 0225 UTC by skeezix »
Minneapolis, MN