I know this is a shortwave forum, but I suspect some of you can shed some
light on this issue. It falls under the heading of "things I can't fix, but
I'm curious anyway".

I'm in Rochester NY. A local rock station, WCMF 96.5, bills itself as having
the most powerful signal in the region. Indeed. It's so powerful that it's
actually distorted when I listen on my car radio. "Like fingernails on a
blackboard" is the most accurate description. Even the voices of the DJs are
distorted, almost like listening to someone who's got phlegm in their
throat, but hasn't cleared it yet. The car radio in question is a stock unit
in a 2002 Toyota Tacoma. I think Panasonic is the mfr. All other stations
sound nice & clean.

Assuming for the moment that the radio isn't at fault, why on earth would a
radio station run their equipment this way?

"Doug Kanter" wrote in message
...

Assuming for the moment that the radio isn't at fault, why on earth would
a
radio station run their equipment this way?

You've designed an imperfect experiment. It is unlikely that the
most-powerful station would sell advertising if their signal sounded as bad
as you describe. If the discussion is about the quality of the signal, other
causes, such as equipment, location (which could result in multipath
interference, such as is observed in urban areas with tall, steel-frame
buildings, or mixing-product intereference caused by proximity to other
strong radio emitters), and user perception must be eliminated. Eg, do other
people using other receivers in other locations in the Rochester area report
similar characteristics of this station's signal? If so, then your
conclusion is valid. I think you're going to find, though, that your
receiver is at fault. It may not be tuning to the station's frequency;
off-frequency tuning of fm signals results in distortion. As it is a car
radio, I assume you are in motion while listening, which would tend to make
multipath, front-end overload, or mixing product interference problems
intermittent and variable.

Laypersons frequently overlook the necessity for scientific rigor when
constructing hypotheses, leading to all sorts of wild ideas and stupid laws.
It may in fact be the case that your local rocker is broadcasting a
distorted signal, but you have not presented sufficient evidence to make
that assertion. Therefore, further discussion of "why" is pointless.

"PM"

1) No experience with other peoples' car radios. I understand that MY car
radio may have problems dealing with the strength of this particular signal.

2) The distortion occurs ALL the time, and NONE of my travels are in the
vicinity of high-rise buildings. However, I'm always within 3-5 miles of the
transmitter, which is on the highest point in this city.

3) I understand all the other possible causes you mention, including the
times when you stop your car and seem to be in a "node" of lousy reception
which is gone when the car moves.

The only other non-scientific clue I have comes from an acquaintance who's
been involved with the radio biz in this city for about 20 years. His highly
rigorous analysis: "They compress the CRAP out of their signal so they can
tell advertisers they'll be heard 90 miles away".


"Paul_Morphy" wrote in message
...

"Doug Kanter" wrote in message
...

Assuming for the moment that the radio isn't at fault, why on earth
would
a
radio station run their equipment this way?

You've designed an imperfect experiment. It is unlikely that the
most-powerful station would sell advertising if their signal sounded as
bad
as you describe. If the discussion is about the quality of the signal,
other
causes, such as equipment, location (which could result in multipath
interference, such as is observed in urban areas with tall, steel-frame
buildings, or mixing-product intereference caused by proximity to other
strong radio emitters), and user perception must be eliminated. Eg, do
other
people using other receivers in other locations in the Rochester area
report
similar characteristics of this station's signal? If so, then your
conclusion is valid. I think you're going to find, though, that your
receiver is at fault. It may not be tuning to the station's frequency;
off-frequency tuning of fm signals results in distortion. As it is a car
radio, I assume you are in motion while listening, which would tend to
make
multipath, front-end overload, or mixing product interference problems
intermittent and variable.

Laypersons frequently overlook the necessity for scientific rigor when
constructing hypotheses, leading to all sorts of wild ideas and stupid
laws.
It may in fact be the case that your local rocker is broadcasting a
distorted signal, but you have not presented sufficient evidence to make
that assertion. Therefore, further discussion of "why" is pointless.

"PM"

Lay off the krank, professor.

On Wed, 21 Apr 2004 14:40:44 GMT, "Paul_Morphy"
wrote:


"Doug Kanter" wrote in message
...

Assuming for the moment that the radio isn't at fault, why on earth would
a
radio station run their equipment this way?

You've designed an imperfect experiment. It is unlikely that the
most-powerful station would sell advertising if their signal sounded as bad
as you describe. If the discussion is about the quality of the signal, other
causes, such as equipment, location (which could result in multipath
interference, such as is observed in urban areas with tall, steel-frame
buildings, or mixing-product intereference caused by proximity to other
strong radio emitters), and user perception must be eliminated. Eg, do other
people using other receivers in other locations in the Rochester area report
similar characteristics of this station's signal? If so, then your
conclusion is valid. I think you're going to find, though, that your
receiver is at fault. It may not be tuning to the station's frequency;
off-frequency tuning of fm signals results in distortion. As it is a car
radio, I assume you are in motion while listening, which would tend to make
multipath, front-end overload, or mixing product interference problems
intermittent and variable.

Laypersons frequently overlook the necessity for scientific rigor when
constructing hypotheses, leading to all sorts of wild ideas and stupid laws.
It may in fact be the case that your local rocker is broadcasting a
distorted signal, but you have not presented sufficient evidence to make
that assertion. Therefore, further discussion of "why" is pointless.

"PM"

"Doug Kanter" wrote in message
...

The only other non-scientific clue I have comes from an acquaintance who's
been involved with the radio biz in this city for about 20 years. His
highly
rigorous analysis: "They compress the CRAP out of their signal so they can
tell advertisers they'll be heard 90 miles away".

Of course, there's no correlation between compression and signal strength,
but advertisers may not understand that. To be fair, Prof. Krank admits that
the signal may be at fault. The frequency deviation may be too high, and
your receiver may have IF filters that are too good for it. Back when Krank
was a lowly lecturer, fm radio was where you went to hear high-fidelity
broadcasting. CHUM-FM in Toronto and the night-time programming on WYSL-FM
in Buffalo were good examples of what rock radio could be. Phil Spector's
"wall of sound" philosophy of over-production was the beginning of the end
of all that.

In closing, Prof. Krank suggests that citizens of the Flower City purchase
CD players.

"PM"

"Doug Kanter" wrote in message
...
1) No experience with other peoples' car radios. I understand that MY car
radio may have problems dealing with the strength of this particular
signal.
Do you perhaps have a $5 radio you can try this station on? Or could you
pick one up?

2) The distortion occurs ALL the time, and NONE of my travels are in the
vicinity of high-rise buildings. However, I'm always within 3-5 miles of
the
transmitter, which is on the highest point in this city.
It's possible being that close that you are getting skywave and groundwave
cross interference, or reflections... though on FM that would be more a
picket fencing effect I would think... Hmm is there another nearby FM
station? (nearby both in frequency and location) You could be getting
splatter off of them affecting your signal.
3) I understand all the other possible causes you mention, including the
times when you stop your car and seem to be in a "node" of lousy reception
which is gone when the car moves.
The only other non-scientific clue I have comes from an acquaintance who's
been involved with the radio biz in this city for about 20 years. His
highly
rigorous analysis: "They compress the CRAP out of their signal so they can
tell advertisers they'll be heard 90 miles away".
What he means is this: An FM signal is 'frequency' modulated, meaning the
signal is splattered over a (compared to other modulation types) large
section of the band. (this is called the envelope... specifically for FM
they refer to it as the 'Deviation' of the signal). When you run a signal
through an amplifier, you have to amplifiy the whole thing; When you amplify
an FM signal by 1000 watts, you are getting less 'effective' amplification
than several other modes, because the signal is wider. If you can compress
the signal by, say, clipping the lows out before it's modulated, or even
just lowering the deviation a bit, you get a higher effective signal level.
This is the magic of Ham radio's CW (morse code) mode, in that it compresses
the signal down to one tiny little spike. If the signal is crunched enough,
audio quality suffers. If the section they transmit is a section the audio
on your radio doesn't do a good job with, it sufferes even more. We have a
local station that band-pass filters everything... they sound like they are
playing at the bottom of a coffee can.
Another possibility is simply the 'front end' of the radio is being over
driven so much it's distorting, or having trouble locking on the signal.. or
perhaps the deviation is too high. Can you hear the signal 'off frequency'?
(tune up or down a bit)
Suggestion: Pick up the cheapest radio you can find at Walmart or Radio
shack. Try and see what happens. I picked up a micro radio as a birthday
present for a friend's kid for $5 on sale at rat shack... think it was
clearance though.

One other thing: look for a 'local' or 'lcl' button on the radio... I just
remembered my car radios have always had them... it's to help with the
clarity of a 'local' radio station I guess. Couldn't hurt to try it.

"David" wrote in message
...
Lay off the krank, professor.

krank?

No thanks. I'm driving.

On Wed, 21 Apr 2004 19:38:41 -0500, "Brian Hill"
wrote:


"David" wrote in message
.. .
Lay off the krank, professor.

krank?

"David" wrote in message
...
No thanks. I'm driving.


Truckers love it.

"Tyas_MT" wrote in message
...
"Doug Kanter" wrote in message
...
1) No experience with other peoples' car radios. I understand that MY
car
radio may have problems dealing with the strength of this particular
signal.
Do you perhaps have a $5 radio you can try this station on? Or could you
pick one up?

2) The distortion occurs ALL the time, and NONE of my travels are in the
vicinity of high-rise buildings. However, I'm always within 3-5 miles of
the
transmitter, which is on the highest point in this city.
It's possible being that close that you are getting skywave and groundwave
cross interference, or reflections... though on FM that would be more a
picket fencing effect I would think... Hmm is there another nearby FM
station? (nearby both in frequency and location) You could be getting
splatter off of them affecting your signal.
3) I understand all the other possible causes you mention, including the
times when you stop your car and seem to be in a "node" of lousy
reception
which is gone when the car moves.
The only other non-scientific clue I have comes from an acquaintance
who's
been involved with the radio biz in this city for about 20 years. His
highly
rigorous analysis: "They compress the CRAP out of their signal so they
can
tell advertisers they'll be heard 90 miles away".
What he means is this: An FM signal is 'frequency' modulated, meaning the
signal is splattered over a (compared to other modulation types) large
section of the band. (this is called the envelope... specifically for FM
they refer to it as the 'Deviation' of the signal). When you run a signal
through an amplifier, you have to amplifiy the whole thing; When you
amplify
an FM signal by 1000 watts, you are getting less 'effective' amplification
than several other modes, because the signal is wider. If you can compress
the signal by, say, clipping the lows out before it's modulated, or even
just lowering the deviation a bit, you get a higher effective signal
level.
This is the magic of Ham radio's CW (morse code) mode, in that it
compresses
the signal down to one tiny little spike. If the signal is crunched
enough,
audio quality suffers. If the section they transmit is a section the audio
on your radio doesn't do a good job with, it sufferes even more. We have
a
local station that band-pass filters everything... they sound like they
are
playing at the bottom of a coffee can.
Another possibility is simply the 'front end' of the radio is being over
driven so much it's distorting, or having trouble locking on the signal..
or
perhaps the deviation is too high. Can you hear the signal 'off
frequency'?
(tune up or down a bit)
Suggestion: Pick up the cheapest radio you can find at Walmart or Radio
shack. Try and see what happens. I picked up a micro radio as a birthday
present for a friend's kid for $5 on sale at rat shack... think it was
clearance though.

One other thing: look for a 'local' or 'lcl' button on the radio... I just
remembered my car radios have always had them... it's to help with the
clarity of a 'local' radio station I guess. Couldn't hurt to try it.



The car radio's the only one I own with that problem. I've tried my Grundig
YB-something around town and it's fine. I guess I have to live with it.
Fortunately, it's not my most important radio station. Not worth pursuing,
other than as a matter of curiosity. I'm currently stuck in an apartment
where security is an issue. I'll be a homeowner (again) shortly, at which
point, along comes a nice Alpine radio. I'd install one now, but my landlord
has issues with tenants shooting thieves in the parking lot, and we have
several of them around here.