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How many AM stations still actively use HD Radio (AM-HD)? Are there any in your area?

The digital artifacts are tough for me to listen to, though. So I have a choice: either digital distortion on 810 when in HD, or FM hiss/noise from the 99-watt FM translator (K237GG) on Lookout Mountain that doesn’t make it much east past downtown Denver. Well, there’s the stream as well but it’s of so-so audio quality at best. I wish it were better.
Yup, the digital artifacts drive me nuts with HD radio. I'll take regular, analog AM any day.

The big HD AM near me, KDKA, is back to just an analog signal, I do believe... Not sure if any other Pittsburgh AMs were ever HD.
 
Yup, the digital artifacts drive me nuts with HD radio. I'll take regular, analog AM any day.

The big HD AM near me, KDKA, is back to just an analog signal, I do believe... Not sure if any other Pittsburgh AMs were ever HD.
Detroit still has at least three:
560 WRDT
910 WFDF
1200 WMUZ

I had all of them lock on my car radio yesterday afternoon while driving along US-23
 
I am going to see who I can hear using HD-AM tonight. Which one(s) am I likely to hear tonight? I am in ZIP 55068 south of Saint Paul Minnesota. I have a Terk AM Advantage with a Sangean HDR-18.

 
I am going to see who I can hear using HD-AM tonight. Which one(s) am I likely to hear tonight? I am in ZIP 55068 south of Saint Paul Minnesota. I have a Terk AM Advantage with a Sangean HDR-18.

I'm about 350 miles due east of the Twin Cities and I was once able to decode WFDF HD at night on a barefoot HDR-16.
 
I've heard ppl say there's a "hash" on either side of an AM-HD station, if the station was on 770 - it'd create noise on 760 & 780, & maybe 750 & 790 as well in Hybrid on a standard radio. AM is just too bandwidth tight for Hybrid it seems. I can't believe they even tried an AM-2, even in Digital Only, there's just not room between 765 & 775 kHz for all that.

The AM systems are probably just old-stock from the late-00s & early-10s at this point that they keep around "just in case" someone needs a replacement, like KSL & the Crawford Stations still on the hybrid system, so the encoders and systems are stuck in that era, while the FM system has been improved on over time and the FM-HD systems are probably newer & better. A lot of the non-car HD Radios available now are old stock too, except Insignia and such.

Huh, that's really not many - I wonder how many FM-HD stations there are in comparison now?

Seems like a LOT of religious stations in California and a few Sports stations in the South have kept the system, from what little I could find.

It'd be a bad move IMO to dump your Analog Audience, AMs are struggling enough already financially. Maybe if you had an HD-2 or HD-3 on a sister station or some FM translators, you might be able to cut the AM signal to Digital-Only. 🤷🏼‍♂️

😂😂😂 IDK what is with the "-1" - sometimes I write "830-HD", sometimes I write "830-1", I think it's because of FM and TV having -1, -2, -3, -4, -5 etc.


The hash some nights was terrible, strong stations would wipe everything out on either side, sounded like jammers. The thing is that the digital hash could travel hundreds of miles at night but the digital signal was lucky to be heard 30-40 miles from the transmitters, really bad system. I'm in Mass and used to get jammed up and down the band at night from the East coast stations, especially the NY stations. Everyone knew it was going nowhere.
 
The San Francisco Bay has zero that I know of. I want to hear it badly too, see if it makes a difference.
We installed HD on 1310. Nautel ND5 transmitters were modified for HD. Lynn managed to build and squeeze in a rotation network in that tiny transmitter building. It worked about better than most of the thirty something HD signals we put on the air. But in the end it was just a giant waste of money. Today it appears the site is not much more than a place to dump stolen cars and for homeless people to hang out.
 
It does. It even has a little of a deadening effect 20 kHz away, though you don't hear the hash there.

Both Crawford and Pillar are running HD day and night in Denver.
In the waning days of San Francisco's KPIG on 1510 AM there was a real problem receiving it because of KFBK's 1530 HD signal. When KFBK shut that down I was able to listen to 1510 all the way up in here Grass Valley (daytime only). Admittedly, that was on a good radio (an old GE Superadio) but it was clean.

Dave B.
 
There must be at least one on 1250 as while I was driving around listening to my local talk station on that frequency the other night the display showed "Need You Now" by Lady A. Interesting that this could pop thru as I could not really hear another station in the background.
 
There must be at least one on 1250 as while I was driving around listening to my local talk station on that frequency the other night the display showed "Need You Now" by Lady A. Interesting that this could pop thru as I could not really hear another station in the background.
HD data/sidebands/signal encompasses mroe than JUST the frequency dead on, so you were picking up a talk station in analog but the data is off to the side so thats how two things at once can happen... but you didnt mention where you are, so its hard to figure out what you heard.

I was 1 1/2 mile from a 250 watt fm translator at 94.5 on a taller tower but had a 110 mile distant HD 2 signal lock on regularly.. and I also had a 1000 mile distant HD2 signal lock on.. again, because what i was hearing was smack dab dead on 94.5 liek the analog was
 
HD Radio tuners are computers and they're known to do odd things like cache data from the previous HD or RDS station you tuned in and then display it even after you've switched to a station that is not transmitting HD or RDS.

If it was actually detecting a digital carrier on 1250 kHz (no stations on that frequency are currently transmitting HD), then you'd see the HD logo appear long before it got a solid enough lock on the data stream to display the station's call letters or other program info.

When tuning in an AM HD signal on my VW's car radio the process was as follows:

1. tune in signal, hear analog audio
2. HD logo appears (dimly) when it detects the digital carrier
3. Station's call letters appear on display
4. After a delay while it builds up the buffer, the HD logo turns brighter and digital audio begins playing
5. Station's additional program data appears on the display
 
HD Radio tuners are computers and they're known to do odd things like cache data from the previous HD or RDS station you tuned in and then display it even after you've switched to a station that is not transmitting HD or RDS.

Actually, they are less like computers and more like a DAC chip that has some defects such as you describe.
If it was actually detecting a digital carrier on 1250 kHz (no stations on that frequency are currently transmitting HD), then you'd see the HD logo appear long before it got a solid enough lock on the data stream to display the station's call letters or other program info.
Sounds like the system stores last used data until it is refreshed. Likely some programmer thought this is desirable.
 
Actually, they are less like computers and more like a DAC chip that has some defects such as you describe.

Sounds like the system stores last used data until it is refreshed. Likely some programmer thought this is desirable.
My Sangean HDT-1X tuner still thinks it can pick up an HD-2 channel at 105.3. That was fine in Oakland; in Denver, that isn't going to work. But, even after I had the tuner in storage for more than a year, it started "thinking" that again right after I plugged it in. I had to re-do the presets and reset the clock, but it was determined to find something at 105.3. Likewise for 97.3 HD-2, but that is valid in Denver.
 
Sounds like the system stores last used data until it is refreshed. Likely some programmer thought this is desirable.
My VW's radio did that. My presets for WCBS (now WHSQ) and WINS still displayed their call letters and the HD logo long after they both switched off HD Radio, until a few seconds after tuning them in when it realized the absence of the HD carrier.

It also cached FM RDS data in the presets, including the 8-character field that is normally scrolled to display artist/title info. My favorite was the preset for 107.1 WWZY, which popped up "Long Joe" every time I pushed it -- which came from them playing the long version of Joe Walsh's "Life's Been Good" when I saved the preset.
 
Actually, they are less like computers and more like a DAC chip that has some defects such as you describe.
They have far more then just a DAC chip. The HD Modules actually contain a CPU and ram. In radios the HD module is separate.

The defects are probably just firmware bugs and not clearing things that they should.
 
In my market we have four AMs that have been off for almost six months and my Kia car radio still displays their logos on those particular frequencies. It also displays a FM in Maryland, the Bay, on 97.7 when we have a country LPFM on that frequency serving some of our rural areas. It must think it matches to that particular call letter.
 
The defects are probably just firmware bugs and not clearing things that they should.
Or it's an efficiency play with caching, i.e., avoiding doing the same work over and over again.
 
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