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Need Some Consistency

I know that HD stations change the program at a moments notice. But this is different. Just turn the HD on and off at a moments notice. There s a station on HD that I like to listen to. But the HD is not consistently on enough to make it dependable. This is no way to make anybody want to listen to HD.
 
I know that HD stations change the program at a moments notice. But this is different. Just turn the HD on and off at a moments notice. There s a station on HD that I like to listen to. But the HD is not consistently on enough to make it dependable. This is no way to make anybody want to listen to HD.
Why not tell us what station it is?
 
I guess you see & hear the HD, then you don't, correct, but you always get the main channel?

Try a different location in your home or whereever you are listening. I have a problem with one station, I lose the HD channels but the main is there all the time, on my outside deck only! I go into the house with the radio and the main channel is there plus the 3 HD channels they have.
Signal strength is stronger in my house too, on this one station!
The station runs about 10kw out of its antenna for its main channel and the HD stations that I get perfect all the time, inside & outside run around 90kw out of their antennas.

You might have a similar problem.

.
 
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This is the radio in my car. When it is out, I try it in several locations while I am driving. I am less than 10 miles from the antenna. When it is out, it is out for real.

When it is there, I can get a lock and decode up to 70 miles out.
 
I believe that would take some new rulemaking by the FCC.
I'm not sure what either of you have in mind, exactly, but the FCC has basically given FM stations the opportunity to have HD coverage that's equivalent to their analog coverage.

The original power level authorized for FM HD was -20 dBc, or 1% of total analog power. It was clear pretty quickly that would be inadequate, and the authorized power level was increased to -14 dBc (4%) and eventually to -10 dBc (10%).

There's pretty conclusive evidence at this point that stations using -10 dBc enjoy digital coverage that's reliable out to their protected analog contour, give or take localized issues with first-adjacent shortspaced interference. As with digital TV, you can get equivalent coverage at a lower power level than analog. You don't need 50 kW of digital power on a class B FM, and it would cause substantial new interference if you did that.

But just because the FCC has authorized stations to increase digital power levels doesn't mean everyone has, or will. Depending on the age of an HD FM installation, there's usually a lot more involved than just turning a knob or clicking a power setting in the GUI. If you have an early space-combined system (separate analog transmitter/line/antenna and digital transmitter/line/antenna), the digital side probably needs at least a new higher-powered transmitter and possibly new line and antenna, too. If you have a more modern combined system, it might not have been spec'ed out with enough headroom for higher digital power. It takes a bigger transmitter to do -10 digital alongside analog, and it's not as simple as just basic math - if you have 20 kW analog TPO and you need 2 kW digital TPO for -10, you need more than a 22 kW transmitter to do it. That's not cheap, and broadcasters aren't exactly swimming in capex money right now to improve installs that are "good enough."

Again - that's on broadcasters at this point. The FCC has given them everything they need from a regulatory standpoint to provide an equivalent digital signal at -10, IF they choose to invest accordingly to make it happen.
 
This is the radio in my car. When it is out, I try it in several locations while I am driving. I am less than 10 miles from the antenna. When it is out, it is out for real.

When it is there, I can get a lock and decode up to 70 miles out.

If it is happening on only one station, I'd call them. I don't know if stations today, have enough people, to talk about a listener's technical issues but when I worked in TV I volunteered to talk to viewers, especially when DTV made its appearance.
I learned from the viewer, and they learned from me.
Today, Radio & TV stations in my area are willing to talk to a listener or viewer about tech issues, maybe the station you are having issues with will talk.

You can also E-mail them (contact them, maybe via their website), this way any tech people there can respond to you when they get time. Point out in the E-mail you need to talk to a tech person that understands your problem after you explain it to them.
 
incI'm not sure what either of you have in mind, exactly, but the FCC has basically given FM stations the opportunity to have HD coverage that's equivalent to their analog coverage.

The original power level authorized for FM HD was -20 dBc, or 1% of total analog power. It was clear pretty quickly that would be inadequate, and the authorized power level was increased to -14 dBc (4%) and eventually to -10 dBc (10%).

There's pretty conclusive evidence at this point that stations using -10 dBc enjoy digital coverage that's reliable out to their protected analog contour, give or take localized issues with first-adjacent shortspaced interference. As with digital TV, you can get equivalent coverage at a lower power level than analog. You don't need 50 kW of digital power on a class B FM, and it would cause substantial new interference if you did that.

But just because the FCC has authorized stations to increase digital power levels doesn't mean everyone has, or will. Depending on the age of an HD FM installation, there's usually a lot more involved than just turning a knob or clicking a power setting in the GUI. If you have an early space-combined system (separate analog transmitter/line/antenna and digital transmitter/line/antenna), the digital side probably needs at least a new higher-powered transmitter and possibly new line and antenna, too. If you have a more modern combined system, it might not have been spec'ed out with enough headroom for higher digital power. It takes a bigger transmitter to do -10 digital alongside analog, and it's not as simple as just basic math - if you have 20 kW analog TPO and you need 2 kW digital TPO for -10, you need more than a 22 kW transmitter to do it. That's not cheap, and broadcasters aren't exactly swimming in capex money right now to improve installs that are "good enough."

Again - that's on broadcasters at this point. The FCC has given them everything they need from a regulatory standpoint to provide an equivalent digital signal at -10, IF they choose to invest accordingly to make it happen.
You've explained it perfectly. Thanks. Radio companies are having enough trouble scraping up advertising for their main signals that throwing big money at HD -- which has barely ever attracted any on its own -- would be absurd. Oh well, so long as the HDs feed analog FM translators, I guess HD will continue to bump along.
 


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