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Feeling A Bit More Positive Towards HD Radio on FM
- Thread starter Barry
- Start date
local oscillator said:
And yet there's a chance the two of you could coexist if the grandfathered station were forced to alter its hd facility to protect your station. That doesn't seem to be happening. Complaints like this are falling on deaf ears at the FCC. The big station could probably reduce (go directional) or eliminate the sideband that's causing your station trouble. They SHOULD, since your station predates the HD sideband.
There's probably a compromise solution somewhere but no one is willing to budge.
For the record, there ARE large swaths of middle America where this first-adjacent channel problem doesn't exist. The only time I hear anything on my market's first adjacents is when the tropo is kicking up, and then it's transient and from 1-2 markets away. We shouldn't be denied a power increase just because it would cause problems in Connecticut or Socal.
No, the power increase on HD should be denied because it exceeds the allowable spectrum. Either enforce the spectrum occupancy rules, or change or eliminate them.
Good points, all.
My station is 34 years old. When we signed on, we knew that there was a big grandfathered first-adjacent signal next to us on the dial that we were going to have to accept. What we didn't bargain for was that decades later it would start spewing its super-powered digital crud right on our channel.
The FCC gets all worked up over the odd half-mile short-spacing on a third-adjacent channel, yet it approves this wholesale destruction of both bands by iBiquity and their junk science. Unbelievable. I'm thankful that market forces are working their magic on HD Radio.
My station is 34 years old. When we signed on, we knew that there was a big grandfathered first-adjacent signal next to us on the dial that we were going to have to accept. What we didn't bargain for was that decades later it would start spewing its super-powered digital crud right on our channel.
The FCC gets all worked up over the odd half-mile short-spacing on a third-adjacent channel, yet it approves this wholesale destruction of both bands by iBiquity and their junk science. Unbelievable. I'm thankful that market forces are working their magic on HD Radio.
There's more than hiss on FM adjacents. There’s the real noise on the host.
Here's a recording off the line output of my car radio from 8 Sept 2011, during the drive home from work about 8 AM.
I spend a few seconds tuning in the new 101.1 news in Chicago, where you can easily hear the interference of the host's own iboc sidebands mixing in "squealies" with audio.
Multipath instances reveal the full iboc buzz.
For some reason this particular station has the worst example of the noise
iboc adds to fm signals.
Then a few seconds of WFMT Classical, where hiss from their own iboc is present (much lower), a few multipath spits....then a few second of someone's
blank carrier, with multipath incidents showing a strong iboc from somewhere, trying to take out the weak carrier.
This is a mono receiver. 2 minute file, 256 k mono. 3.9 mb.
http://www.sendspace.com/file/c6sniy
Here's a recording off the line output of my car radio from 8 Sept 2011, during the drive home from work about 8 AM.
I spend a few seconds tuning in the new 101.1 news in Chicago, where you can easily hear the interference of the host's own iboc sidebands mixing in "squealies" with audio.
Multipath instances reveal the full iboc buzz.
For some reason this particular station has the worst example of the noise
iboc adds to fm signals.
Then a few seconds of WFMT Classical, where hiss from their own iboc is present (much lower), a few multipath spits....then a few second of someone's
blank carrier, with multipath incidents showing a strong iboc from somewhere, trying to take out the weak carrier.
This is a mono receiver. 2 minute file, 256 k mono. 3.9 mb.
http://www.sendspace.com/file/c6sniy
1972 Dodge Dart with factory Motorola AM/FM...the first model that used an integrated circuit!
It has been a really great dx radio for many years, but the wideband (apparently) IF doesn't
play well with so much noise so close in to the desired.
It seems to have a lot louder spits and spurts on multipath flutter since "the great change".
For some reason the 101.1 signal is outstandingly bad in this respect.
On most FMs it's not very noticable at all. Like the WFMT classical portion.
It has been a really great dx radio for many years, but the wideband (apparently) IF doesn't
play well with so much noise so close in to the desired.
It seems to have a lot louder spits and spurts on multipath flutter since "the great change".
For some reason the 101.1 signal is outstandingly bad in this respect.
On most FMs it's not very noticable at all. Like the WFMT classical portion.
WXRT 93.1 sounded kinda of weird this morning on the way home from work, so I turned on the recorder.
What in the world is happening with this Led Zeppelin cut?
Is this just odd processing or are we hearing the rasp of the sidebands modulating the cymbals?
Two minute 256kb mp3 in mono
http://www.sendspace.com/file/oohxz0
What in the world is happening with this Led Zeppelin cut?
Is this just odd processing or are we hearing the rasp of the sidebands modulating the cymbals?
Two minute 256kb mp3 in mono
http://www.sendspace.com/file/oohxz0
Got through about :45, and then two of my teeth broke.
That's pretty bad. I've heard crispy highs like that before but never put it with HD so I'll have to pay attention next time and see if it's only on ones running HD.
With these samples I feel compelled to at least post this scoped recording I did of a local station that flipped to the Cumulus "Journey" 80s/90s format that was recorded in HD via the Insignia portable radio. Granted there's not much music here since it's all jingles, announcers and local commercials, but the bits of music sound really good. Even despite being a 128 kbps mp3 file. No funny business beyond the minor artefacting from the cascading compression schemes. Between the bad analog processing of that classic rock clip or this slightly swishy HD, I'll take the HD. Not the least of which is for the rock bottom noise floor and a bit better stereo separation.
The mp3 file is 128 kbps and 9:55 long.
With these samples I feel compelled to at least post this scoped recording I did of a local station that flipped to the Cumulus "Journey" 80s/90s format that was recorded in HD via the Insignia portable radio. Granted there's not much music here since it's all jingles, announcers and local commercials, but the bits of music sound really good. Even despite being a 128 kbps mp3 file. No funny business beyond the minor artefacting from the cascading compression schemes. Between the bad analog processing of that classic rock clip or this slightly swishy HD, I'll take the HD. Not the least of which is for the rock bottom noise floor and a bit better stereo separation.
The mp3 file is 128 kbps and 9:55 long.
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