Is HD Radio in full coverage now?

I was shocked when I test drove a Ford today to see they have HD on it also. When we parked it back at the shop I put it on KONO, we are about 60 or so miles away from San antonio, it was pulling in KONO's HD signal. It stayed on to. If it is in full power now I may hook my radio back up.

It varies from station to station just as it always has. It's been my experience that about half the HD stations in my area are running higher power of some form, from just 1.1% to 4%. Of course, the other half are all shut down and analog only again, so…

jras20 said:

I was shocked when I test drove a Ford today...

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One should always avoid direct contact with the spark plugs while the engine is running.

Jras:
I have been a user of HD using KILT FM HD3 to listen to Sportsradio 610 on FM at night. I have been pleased to always hold the HD going south until Wharton or El Campo at the least. Good for Texans coverage after the game.

Clouseau

I'm getting the car . I may hook my HD Radios back up if the power has improved since the last time I had it hooked up it's been a while.

With more cars coming with HD Radio, will this help people get more interested? I wish there was more sub channels out there.

Just to clarify.. AM and FM HD are two completely different animals from the station-transmission perspective. FM stations have the option to increase their HD (IBOC) power because they use a completely separate transmitter for the digital portion of the FM signal. AM never has had that option, as the digital portion are sidebands modulated in the same carrier. I know it's easy to assume HD radio to be one category from a listener or car owner perspective, but they're not the same technically.

Most FM stations that I know are using the same transmitter for analog and digital generation. I have a Nautel running analog with 4% digital.

My point being.. If one wants to pursue increasing the output of the FM HD portion of the signal, one either needs to purchase a much larger single (or combined) transmitter (expensive if your analog transmitter is under ten years old), or use a second digital transmitter running into a second antenna or hybrid combiner. With AM, your only choice is to modulate the HD sidebands in the same exciter/transmitter. That is your only choice and you can't exceed the total licensed output power analog and digital combined.

A friend of mine, who's native language and his wife's only language is Russian, was and remains delighted by my having introducing him to a Miami station which carries Danu Radio on their HD3, even though he had had the car for several months, so not everyone is finding the sub-channels on their own.

ai4i said:

...on their HD3...

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I meant 103.5-HD2.

It may require an all-digital transition just like TV had in 2009 (and now LPTV once the repacking mess is taken care of). Hybrid operation is like introducing the color subcarrier and Digital TV transition companion channels at the same time.

KTN Corp said:

It may require an all-digital transition just like TV had in 2009 ...

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That might be more difficult than the TV transition was. TVs just sit on a table or console or in an entertainment system. It's easy to put a new TV where an old one was. Car radios in the dash are much more difficult to replace.

HD - when it works - sounds great. 60 miles for KONO doesn't surprise me, but at least if it goes out you don't have to worry about silence, you will get analog from the station. I can get about 70 to 75 miles FM HD - but that is with a top of the line Pioneer Supertuner 3D with a whip antenna, not some stock radio the auto maker puts in and their ridiculous shark fin / nub antenna. My daughter's boyfriend bought a truck with HD and one of those shark fin antennas, HD drops out badly on KSBJ only 50 miles away. Since she is only interested in NGEN - neither of them can listen to it with dropouts. KUHA cannot come soon enough for them!!!! I still get HD dropouts in sight of the antennas, depending on if it is a low spot, I get jammed by the local oscillator in a car nearby, or some unknown factor. There are two types of dropouts - one where the digital data stream is recoverable and it comes back in less than a second, and ones where the digital data stream is unrecoverable and it has to re-sync on it from scratch - AFTER the interference / dropout situation has resolved. So when I state HD range of 70-75 miles, I am really talking about a locked HD signal that isn't dropping. After that, the HD dropouts are too severe to allow enjoyable listening. Up to 30 seconds with no HD. But that can happen as close as 20 miles from the Missouri City sticks - and since I listen to HD-2 almost exclusively, it is NOT enjoyable to have dropouts to silence. My wife has NO tolerance for HD-2 dropouts and insists I change the station to something reliable. I suspect most non-DX'ers have similar tolerance to something that doesn't work.

The HD2 is the same data stream as the HD1. Losing a stream close in to a TX site is usually caused by severe multipath. In your case, I suspect any issues may be because you did the radio installation, not a factory one provided by the vehicle manufacturer.

Kelly A said:

The HD2 is the same data stream as the HD1. Losing a stream close in to a TX site is usually caused by severe multipath. In your case, I suspect any issues may be because you did the radio installation, not a factory one provided by the vehicle manufacturer.

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Well, any car radio that gets clear, static free reception of WBAP along I-10 in Houston, and pulls in FM from over 100 miles away (used to be 150 before Cypress radio covered 103.5), and gets sporadic reception of 94.9 from Dallas has a good antenna installation and good grounding. My wife's factory installed Delco, even with a whip, is deaf on AM, and FM is nowhere near as good. My daughter's car is adequate on AM and FM for a shark fin, but still so-so. My GE SR 3 portable gets more stations. Her boyfriend's truck, 2015 model with all the sound upgrades, is still limited on AM and FM.

Local oscillator jamming can happen anywhere - it is annoying because I get jammed at a light, and the HD stays jammed until the offending car moves away. Sometimes it takes 100 feet or more. Invarriably, the same car ends up near me again at the next light. I've done the experiment, parking one car one, two, three houses down - the local oscillator jamming effect is real. I will probably post a Youtube of the experiment soon. Just for good measure, I tried a couple of different cars - RF leakage from the local oscillator is less on one that the other, both jamming cars had stock - non HD radios jamming my HD radio. I ran inside to check on a home HD tuner, it is jammed by a car parked in front. All that is needed is 10.4 to 11.0 MHz difference in frequency.

Some dropouts appear to be elevation related, I notice that the dropouts I am getting only 20 miles out from the full class C stations correspond to areas that recently flooded - they are low areas. I still don't think I am losing line of sight, but with houses and businesses everywhere, I may be dipping below the event horizon. I think most of the HD stations around here are running enhanced power, but it doesn't help much.

I've tried multiple times with more than one radio to replicate that local oscillator issue and have never had any issues arise.

That's because like many of his claims, this problem doesn't actually exist

Kelly A said:

That's because like many of his claims, this problem doesn't actually exist

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You just motivated me to get that youtube on the web proving the issue. I tried to do good science. The only thing I can't prove is undertone jamming from stations 10.4 to 11 MHz above the received HD signal. I need to try that test again, because dropouts are happening on KSBJ 89.3, and 100.3 is a popular local station, not so much 99.7.

It wouldn't surprise me if some of the car radio manufacturers are using low side injection instead of high side injection - for whatever reason.