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Paul Del Priore February 4th 08 07:45 AM

Auto Antenna
 
I have a new Lexus 400h and live a distance away from the FM stations I like
to listen to. Reception is very poor very dependent on direction of vehicle.
I blame the window antenna. Would I be better off with a whip antenna?

Paul



Ross Herbert February 4th 08 09:34 AM

Auto Antenna
 
On Mon, 4 Feb 2008 01:45:53 -0500, "Paul Del Priore"
wrote:

:I have a new Lexus 400h and live a distance away from the FM stations I like
:to listen to. Reception is very poor very dependent on direction of vehicle.
:I blame the window antenna. Would I be better off with a whip antenna?
:
:Paul
:

Not necessarily. Will depend on transmitted FM power, distance from Tx, and
intervening terrain between Tx and Rx antenna.

How far is "quite a distance"?

Jakthehammer February 4th 08 11:26 AM

Auto Antenna
 

"Ross Herbert" wrote in message
...
On Mon, 4 Feb 2008 01:45:53 -0500, "Paul Del Priore"

wrote:

:I have a new Lexus 400h and live a distance away from the FM stations I
like
:to listen to. Reception is very poor very dependent on direction of
vehicle.
:I blame the window antenna. Would I be better off with a whip antenna?
:
:Paul
:

Not necessarily. Will depend on transmitted FM power, distance from Tx,
and
intervening terrain between Tx and Rx antenna.

How far is "quite a distance"?


By design FM transmitters are not designed to go very far. Antenna will
not help.

ONLY AM, SHORTWAVE, SSB, and MICROWAVE. The 2 Meter can go far because of
the repeater station, but that's a different story.

Yak...


mc February 4th 08 03:43 PM

Auto Antenna
 
"Paul Del Priore" wrote in message
...
I have a new Lexus 400h and live a distance away from the FM stations I
like to listen to. Reception is very poor very dependent on direction of
vehicle. I blame the window antenna. Would I be better off with a whip
antenna?


Probably, but you may also have a defective radio. If an FM radio loses one
or two transistors, often the only symptom is a loss of sensitivity.
Compare to another car radio in the same location tuned to the same
stations.

How far away are your stations? FM signals travel in straight line-of-sight
paths -- there is no ground wave as with AM, nor ionospheric reflection. 50
miles is about the limit.



mc February 4th 08 03:45 PM

Auto Antenna
 
By design FM transmitters are not designed to go very far. Antenna will
not help.

ONLY AM, SHORTWAVE, SSB, and MICROWAVE. The 2 Meter can go far because
of
the repeater station, but that's a different story.


It's not the way the transmitters are designed, it is the behavior of the
earth and its atmosphere at those frequencies. The transmitters are
actually very powerful.

For broadcasting, limited, predictable range is a good thing because it
allows another station to be on the same frequency 100 or 150 miles away
without interfering with it.

Microwaves are even worse -- they travel only in a straight line -- which is
why microwave towers are tall and have antennas aimed directly at each
other. But in that situation the transmitters don't have to be very
powerful.




jakdedert February 4th 08 07:07 PM

Auto Antenna
 
Paul Del Priore wrote:
I have a new Lexus 400h and live a distance away from the FM stations I like
to listen to. Reception is very poor very dependent on direction of vehicle.
I blame the window antenna. Would I be better off with a whip antenna?

Paul


Although I'm not suggesting you cut holes in your new Lexus, when
windshield antennas first came out in the 70's, I made a good bit of
money replacing them with whips. They may have improved since, but back
then, there was always a significant improvement in reception.

Comments in the thread about checking the existing antenna is
well-advised, however.

jak

Dave Plowman (News) February 4th 08 08:12 PM

Auto Antenna
 
In article ,
Paul Del Priore wrote:
I have a new Lexus 400h and live a distance away from the FM stations I
like to listen to. Reception is very poor very dependent on direction
of vehicle. I blame the window antenna. Would I be better off with a
whip antenna?


Yes. But a fixed roof mounted one is the ideal - uses the roof as a ground
plane.

--
*Why is the third hand on the watch called a second hand?

Dave Plowman London SW
To e-mail, change noise into sound.

Paul Del Priore February 4th 08 09:54 PM

Auto Antenna
 
Jak,
I did have Lexus check out the system and they claim it is "working as
designed". Since a whip is omnidirectional and the windshield antenna is
directional at least car direction would not cause reception problems. From
your experience it would seem that the gain of the whip is as good or better
than the windshield type. Would you agree with that?

Paul


"jakdedert" wrote in message
. ..
Paul Del Priore wrote:
I have a new Lexus 400h and live a distance away from the FM stations I
like to listen to. Reception is very poor very dependent on direction of
vehicle. I blame the window antenna. Would I be better off with a whip
antenna?

Paul

Although I'm not suggesting you cut holes in your new Lexus, when
windshield antennas first came out in the 70's, I made a good bit of money
replacing them with whips. They may have improved since, but back then,
there was always a significant improvement in reception.

Comments in the thread about checking the existing antenna is
well-advised, however.

jak




GregS[_3_] February 4th 08 10:13 PM

Auto Antenna
 
In article , "Paul Del Priore" wrote:
Jak,
I did have Lexus check out the system and they claim it is "working as
designed". Since a whip is omnidirectional and the windshield antenna is
directional at least car direction would not cause reception problems. From
your experience it would seem that the gain of the whip is as good or better
than the windshield type. Would you agree with that?

Paul



Whips are omni but are rarely placed on an unobstructed surface. Verticals
have more noise than a horzontal. Vertical placed in the center of the roof would be best, about
29 inches long.

greg

"jakdedert" wrote in message
...
Paul Del Priore wrote:
I have a new Lexus 400h and live a distance away from the FM stations I
like to listen to. Reception is very poor very dependent on direction of
vehicle. I blame the window antenna. Would I be better off with a whip
antenna?

Paul

Although I'm not suggesting you cut holes in your new Lexus, when
windshield antennas first came out in the 70's, I made a good bit of money
replacing them with whips. They may have improved since, but back then,
there was always a significant improvement in reception.

Comments in the thread about checking the existing antenna is
well-advised, however.

jak




Don Bowey February 4th 08 10:20 PM

Auto Antenna
 
On 2/4/08 2:26 AM, in article , "Jakthehammer"
wrote:


"Ross Herbert" wrote in message
...
On Mon, 4 Feb 2008 01:45:53 -0500, "Paul Del Priore"

wrote:

:I have a new Lexus 400h and live a distance away from the FM stations I
like
:to listen to. Reception is very poor very dependent on direction of
vehicle.
:I blame the window antenna. Would I be better off with a whip antenna?
:
:Paul
:

Not necessarily. Will depend on transmitted FM power, distance from Tx,
and
intervening terrain between Tx and Rx antenna.

How far is "quite a distance"?


By design FM transmitters are not designed to go very far. Antenna will
not help.

ONLY AM, SHORTWAVE, SSB, and MICROWAVE. The 2 Meter can go far because of
the repeater station, but that's a different story.

Yak...


Total BS.

Please disregard this guy.


Jakthehammer February 4th 08 10:31 PM

Auto Antenna
 

"mc" wrote in message
. ..
By design FM transmitters are not designed to go very far. Antenna
will
not help.

ONLY AM, SHORTWAVE, SSB, and MICROWAVE. The 2 Meter can go far because
of
the repeater station, but that's a different story.


It's not the way the transmitters are designed, it is the behavior of the
earth and its atmosphere at those frequencies. The transmitters are
actually very powerful.



If your logic is true then why FM cannot defeat other modulation? Assuming
they all have equal RF wattages?

FYI - You preaching to the guy who built Powerful RF transmitters, minimum
5Kw.


mc February 4th 08 11:51 PM

Auto Antenna
 
"Jakthehammer" wrote in message
...

"mc" wrote in message
. ..
By design FM transmitters are not designed to go very far. Antenna
will
not help.

ONLY AM, SHORTWAVE, SSB, and MICROWAVE. The 2 Meter can go far because
of
the repeater station, but that's a different story.


It's not the way the transmitters are designed, it is the behavior of the
earth and its atmosphere at those frequencies. The transmitters are
actually very powerful.


If your logic is true then why FM cannot defeat other modulation?
Assuming
they all have equal RF wattages?


You're not expressing yourself very clearly. "FM" is both a modulation
technique and (in much of the world) a broadcast frequency band.
Propagation is largely a matter of frequency. It is true that FM does not
perform as well with weak signals as AM, which in turn is not as good as
SSB.



mc February 4th 08 11:53 PM

Auto Antenna
 
Note that you could experiment with a vertical antenna without drilling into
the car. Get a magnet-mount ham radio antenna and change the whip so it is
30 inches long. Of course, you will still have to gain access to the
antenna connector on the radio -- which is probably not hard; most newer car
radios pull out forward if you use the appropriate special tools to unlock
them.



Michael A. Terrell February 8th 08 05:20 PM

Auto Antenna
 
Jakthehammer wrote:

By design FM transmitters are not designed to go very far.



Idiot. It's obvious that you have never worked in broadcast. C-band
TV transponders are about 10 watts at 4 GHz, and the 20 MHz wide FM
signal travels over 11,000 miles from the bird to the receiving antenna.

A local UHF station's tower is in Orange City, Florida. We received
a reception report from the Dallas / Ft. Worth area from a man who
watched our station for over six hours one evening.

I know that this isn't normal reception, and was at a time of high
sunspot activity, but the point is that you can't make blank,
meaningless statements like: "By design FM transmitters are not designed
to go very far."


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

Michael A. Terrell February 8th 08 05:32 PM

Auto Antenna
 
Jakthehammer wrote:

"mc" wrote in message
. ..
By design FM transmitters are not designed to go very far. Antenna
will
not help.

ONLY AM, SHORTWAVE, SSB, and MICROWAVE. The 2 Meter can go far because
of
the repeater station, but that's a different story.


It's not the way the transmitters are designed, it is the behavior of the
earth and its atmosphere at those frequencies. The transmitters are
actually very powerful.


If your logic is true then why FM cannot defeat other modulation? Assuming
they all have equal RF wattages?



What the hell is "FM cannot defeat other modulation" supposed to
mean? Do you have ANY idea about capture effect, quieting, receiver
desensing, or other real world problems that affect clear reception on a
car radio? A local TV station on Channel six can desese the low end of
the FM band. Other high level noise sources can wipe out most, or all
of the FM band.


FYI - You preaching to the guy who built Powerful RF transmitters, minimum
5Kw.



You think 5 KW is powerful? You say absolutely NOTHING about the
application, the tower height, antenna type, feedline loss, or a hundred
other details. Try building a 5 MW EIRP UHF TV station with a 1749 foot
AAT antenna. Or even a 1.3 MW EIRP UHF TV station on a 300 ft tower.

BTW, that 1749 foot AAT TV tower also had five of the Orlando FM
stations at the site, fed to a curtain antenna at 1200 feet AAT. The
combiner had three more ports for either standby transmitters, or to add
more stations.

--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

Bob February 9th 08 07:29 PM

Auto Antenna
 
On Feb 4, 1:45 am, "Paul Del Priore"
wrote:
I have a new Lexus 400h and live a distance away from the FM stations I like
to listen to. Reception is very poor very dependent on direction of vehicle.
I blame the window antenna. Would I be better off with a whip antenna?

Paul


All of you missed the point. Just buy an American car. One of the
best things we can do to help our economy & our country. And if you
are going to tell me that many American cars are built in another
country, you don't understand the bigger picture of the economics.


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