Explain This?

[Arp2]

I took a drive over the weekend to check out a small cluster and had a strange experience with one of the stations.

Approaching from the south and east, I noticed the station had an awful audio problem in which the low end was pretty much nonexistant and the rest sounded strangely...squished. Almost like "out of phase" but not. The strange part? As I drove around to keep listening, it was fine to the north and west and within a couple miles of the tower....not "great," but certainly not like the other directions. And this one station was the only one on the tower that sounded like that.

Class A....two bays....radomes.....south side of tower......anything?

[Hoosier Daddy]

WXZQ, Waverly?

[Arp2]

Stop it.........................................................


You mean this happens other places with some regularity? I've never heard it before. Once I find out what this is, I'll have to remember to thank every engineer I've ever known for not allowing it.....

[Jet Black]

Interference from Flying Saucers?

[genlock]

I have ordered the sporadic-e interference to be stopped immediately.
If it does not stop, it is the fault of disloyal or lazy subordinates.

[Cameron]

I had a Camry radio that needed an "override" switch because it insisted on narrowbanding and blending to mono in order to hang on to an FM signal.
This may be happening to you as a result of multipath, low signal level, interference, or some craptacular L+R information in the wiring/processing that makes the blend to mono funky.
The bandwidth reduction may be a result of the radio sacrificing bandwidth in order to hang on to the station.
Some wierdness is a result of some digital signal processing in some car sound-system options that adjust audio based on outside/inside noise and some that add surround-effects to "sweeten" the sound.

Again Toyota's "premium" JBL package has DSP that really changes the way stations sound. It's really kind of a "stereo-wide" effect.

[Big Media]

If this was WZJO, aka Z-Rock 94.5, this is normal. It's like they run their audio through a band-pass filter or something.

[Arp2]

...it insisted on narrowbanding and blending to mono in order to hang on to an FM signal.
This may be happening to you as a result of multipath, low signal level, interference, or some craptacular L+R information in the wiring/processing that makes the blend to mono funky.

Thanks, Cameon...that's interesting....I hadn't thought about the blend to mono.

I'm still curious, though. The tower is about 10 miles away from any buildings taller than 30 or 40 feet, and, topographically, I don't think there was anything significant to the south and east. The land is just slightly rolling with probably little more than 50 or 60 feet of variation any direction you would go, and the problem was there as little as three miles out. If any direction, I'd say the land got higher to the north. So something might be wrong that makes its "not-even-quite-a-normal-'old'-class-A" signal even less than what it should be.(?) Preliminarily, technically, I'm assuming "problems....lotsa problems!"

The bandwidth reduction may be a result of the radio sacrificing bandwidth in order to hang on to the station.

Everything else was fine-ish...even class A's coming in from 50+ miles away. I'll admit I can be fooled as the blending occurs and the stereo light stays on, but, in this case, I don't think it was my radio or my ears. Like I said, I've never heard anything like this before. The closest analogy I can make might be a concert sound system that has a bass bin or two out of phase...most sections of the venue sound fine, but, as you move through a particular area of the seating,....

[Cameron]

Well come to Huntington and re-callibrate your radio with 101.5's and 97.9's 120% modulation.
Set the low-end at WMUL's 80%.
+20 on MUL and -20 on Connoisseur will give you a baseline for 100% modulation.
That outta' knock it back into shape.

[Arp2]

Generally speaking, one doesn't need to travel from home these days to hear overmodulation!

[Clay JD Walker]

Add a CC Composite clipper, and an overdriven, bitstarved HD, you're in Greensboro...totally unlistenable...I betcha females LOVE listening at 120% modulation, huh?

[engineer]

I miss the good ole days when loudness wars meant building an air chain that was loud and legal. Back then, everyone had TFT's or QEI's and could monitor each other. The FCC also was still in the business of caring about modulation. Still to this day I can't reveal the calls, but it's a popular 100kW in western VA where I had the loudest chain possible. Started with heavily modified Texar's (Monroeville with DVE mods) into Dorrough 610's, into a modified 8100, into a modified CP803, then into a Somich Fleximod. The Fleximod was an updated DBE-1000 used at Z100 in NYC. It rocked, and was several dB louder than anything on the dial at 100% !

Today, people just jack up the modulation which is most often evident by the 15 or 20% pilot. They are not smart enough to match the pilot to the modulation level, nor do they care. It really sounds like crap on cheap radios.