On Sat, 25 Jun 2005 18:24:43 -0400, "Robert Morein"
wrote:


"ric" wrote in message ...
Robert Morein wrote:

You can do it yourself. Take a look at
http://www.ycars.org/EFRA/Module%20C/AntDip.htm

The wavelength of 88.3 mHz is 66.88 inches. Your dipole should be 1/2
that
length: 33.5.

Hmmm...the website you give above contradicts that. It says:

1/2 WL dipole length = 468/f = 468/88.3 = 5.3 feet = 63.6 inches.

Since none of the existing FM dipoles I have are 63.6 inches long (the
longest being just under 5 feet), should I assume that is why they are
so poor in the "college" (88-90 MHz) FM band?

I'm sorry, Ric. I made a mistake.
The folded dipole is cut to 1/4 wavelength, which is why it works out to
33.5 inches for your frequency of interest.

********! 1,2,3,4. . .mistakes.

Margaret von B. wrote:

How many vacuum tubes did you find in it?

A little math. Simple, really. Each frequency has
a specific length of antenna that it is received best at,
so match your antenna to your station and presto.

Or didn't you ever think of shortening the antenna?
It does telescope for a reason, you know.

ric wrote:

Joseph Oberlander wrote:


Thanks. Are you familiar with the FM-2G-C?

http://www.fanfare.com/fm-2g-c.html

I am leaning toward trying it, indoors (next to a window) first.

Their marketing is rubbish, btw. Any standard "whip" type
antenna will work like that - just shorten it to the exact
frequency that you desire and aim it around until you get a
good signal.


A lower frequency requires a *shorter* antenna?? I thought it would
have to be *longer*. Please explain.

Sorry - I got it reversed. but the theory is the same - find
the right length and make it so. Then aim.

ric wrote:

Robert Morein wrote:


You can do it yourself. Take a look at
http://www.ycars.org/EFRA/Module%20C/AntDip.htm

The wavelength of 88.3 mHz is 66.88 inches. Your dipole should be 1/2 that
length: 33.5.


Hmmm...the website you give above contradicts that. It says:

1/2 WL dipole length = 468/f = 468/88.3 = 5.3 feet = 63.6 inches.

Since none of the existing FM dipoles I have are 63.6 inches long (the
longest being just under 5 feet), should I assume that is why they are
so poor in the "college" (88-90 MHz) FM band?

Ah. you *can* get 6 fters. They are custom parts, though, and not
sold at Radio Shack and simmilar places.

Joseph Oberlander wrote:

1/2 WL dipole length = 468/f = 468/88.3 = 5.3 feet = 63.6 inches.

Since none of the existing FM dipoles I have are 63.6 inches long (the
longest being just under 5 feet), should I assume that is why they are
so poor in the "college" (88-90 MHz) FM band?

Ah. you *can* get 6 fters. They are custom parts, though, and not
sold at Radio Shack and simmilar places.

Even the $25 "FM Select" dipole has only a 54" element. That's optimized
for 104 MHz. No thanks.

http://www.ccrane.com/fm-reflect-antenna.aspx

"Joseph Oberlander" wrote in message
ink.net...


ric wrote:

Joseph Oberlander wrote:


Thanks. Are you familiar with the FM-2G-C?

http://www.fanfare.com/fm-2g-c.html

I am leaning toward trying it, indoors (next to a window) first.

Their marketing is rubbish, btw. Any standard "whip" type
antenna will work like that - just shorten it to the exact
frequency that you desire and aim it around until you get a
good signal.


A lower frequency requires a *shorter* antenna?? I thought it would
have to be *longer*. Please explain.

Sorry - I got it reversed. but the theory is the same -

As I said before, to call you an idiot would be an insult to idiots.

Margaret

Margaret von B. wrote:
"Joseph Oberlander" wrote
in message

ink.net...


ric wrote:

Joseph Oberlander wrote:


Thanks. Are you familiar with the FM-2G-C?

http://www.fanfare.com/fm-2g-c.html

I am leaning toward trying it, indoors (next to a
window) first.

Their marketing is rubbish, btw. Any standard "whip"
type
antenna will work like that - just shorten it to the
exact
frequency that you desire and aim it around until you
get a
good signal.


A lower frequency requires a *shorter* antenna?? I
thought it would
have to be *longer*. Please explain.

Sorry - I got it reversed. but the theory is the same -

As I said before, to call you an idiot would be an insult
to idiots.

Maggie is obviously yet another graduate of the Middius
school of tact and charm...

"Joseph Oberlander" wrote in message
ink.net...


Margaret von B. wrote:

How many vacuum tubes did you find in it?

A little math. Simple, really.

Simple, stupid and wrong - your trademark.


Margaret

"Arny Krueger" wrote in message
...
Margaret von B. wrote:

As I said before, to call you an idiot would be an insult
to idiots.

Maggie is obviously yet another graduate of the Middius
school of tact and charm...


Hah!
Thanks for admitting you were offended!!
Haw, haw, haw.



----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups
----= East and West-Coast Server Farms - Total Privacy via Encryption =----

Arny Krueger wrote:
Margaret von B. wrote:
"Joseph Oberlander" wrote
in message

ink.net...


ric wrote:

Joseph Oberlander wrote:


Thanks. Are you familiar with the FM-2G-C?

http://www.fanfare.com/fm-2g-c.html

I am leaning toward trying it, indoors (next to a
window) first.

Their marketing is rubbish, btw. Any standard "whip"
type
antenna will work like that - just shorten it to the
exact
frequency that you desire and aim it around until you
get a
good signal.


A lower frequency requires a *shorter* antenna?? I
thought it would
have to be *longer*. Please explain.

Sorry - I got it reversed. but the theory is the same -

As I said before, to call you an idiot would be an insult
to idiots.

Maggie is obviously yet another graduate of the Middius
school of tact and charm...


I wonder if she'll do the "Middius Meltdown" for us some day soon?
:-D

Clyde Slick wrote:
"Arny Krueger" wrote in message
...
Margaret von B. wrote:

As I said before, to call you an idiot would be an
insult
to idiots.

Maggie is obviously yet another graduate of the Middius
school of tact and charm...


Hah!
Thanks for admitting you were offended!!
Haw, haw, haw.

Offended? No, but I did feel a profound sense of pity for
Maggie. Not only is she burdened with her own faults, but
she's picked up a boatload of new faults from Middius.

"Arny Krueger" wrote in message
...
Clyde Slick wrote:
"Arny Krueger" wrote in message
...
Margaret von B. wrote:

As I said before, to call you an idiot would be an
insult
to idiots.

Maggie is obviously yet another graduate of the Middius
school of tact and charm...


Hah!
Thanks for admitting you were offended!!
Haw, haw, haw.

Offended? No, but I did feel a profound sense of pity for
Maggie. Not only is she burdened with her own faults, but
she's picked up a boatload of new faults from Middius.



The Big Stilton is just boiling in his loneliness. As he put it so
eloquently a couple of days ago "why aren't I getting more love?" Come to
think of it, I have to let the dogs out to make sure there are no Dahmer
looking things "with or without rain coats" hiding in the bushes.

A girl has to take certain precautions these days, you know. :-)

And dear Arny, since I know you're reading this, you should really consider
joining an ***adult*** masturbation circle. Menopause is a long and hard
ordeal for both parties. I'm praying for you and your wife.

Cheers,

Margaret

On Wed, 22 Jun 2005 20:56:44 -0400, "Robert Morein"
wrote:


The twinlead
from a folded dipole is part of the antenna system itself. Therefore, it
picks up more signal, which can cancel with that received by the nominal
antenna.

********! (7)
It is a balanced transmission line which is matched to the balanced
300ohm folded dipole. The fields associated with the twin conductors
of the feeder cancel in the far field. It cannot radiate/recieve
itself if it is properly balanced.

Back in the 60's, people would prewire their houses with twinlead
for a rooftop TV antenna, and the ghosting (visual multipath) was vicious.
Replacing it with coax eliminated the distribution system as a secondary
antenna.


"twinlead" has lower losses than coax, (for similar size/cost)
however the disadvantage is that the fields extend outside the bounds
of the cable, whereas with coax it is within. To get the best out of
balanced feed it should be spaced away from other materials. Coax can
be attached to walls, taped to metal poles, etc. It also needs a
decent balun to connect to a dipole.

On Sat, 25 Jun 2005 23:10:02 GMT, ow
(Goofball_star_dot_etal) wrote:

On Sat, 25 Jun 2005 18:24:43 -0400, "Robert Morein"
wrote:

I'm sorry, Ric. I made a mistake.
The folded dipole is cut to 1/4 wavelength, which is why it works out to
33.5 inches for your frequency of interest.

********! 1,2,3,4. . .mistakes.


See: http://www.ee.surrey.ac.uk/Personal/...es/rodres.html

On Tue, 21 Jun 2005 02:38:10 -0400, "Robert Morein"
wrote:

There really isn't.
It is a common misconception that a station is not received due to
inadequate signal strength. This is actually quite rare.

******** (run out of fingers)

It is the rule that the vast majority of VHF stations are out of
range.

Joseph Oberlander wrote:

Their marketing is rubbish, btw. Any standard "whip" type
antenna will work like that - just shorten it to the exact
frequency that you desire and aim it around until you get a
good signal.


A lower frequency requires a *shorter* antenna?? I thought it would
have to be *longer*. Please explain.

Sorry - I got it reversed. but the theory is the same - find
the right length and make it so. Then aim.

Sorry, but I am having trouble figuring out how to extend a whip
antenna to a length longer than its maximum. Hints?

"Goofball_star_dot_etal" wrote in message
...
On Tue, 21 Jun 2005 02:38:10 -0400, "Robert Morein"
wrote:

There really isn't.
It is a common misconception that a station is not received due to
inadequate signal strength. This is actually quite rare.

******** (run out of fingers)

It is the rule that the vast majority of VHF stations are out of
range.

The range is usually not determined by signal strength. It is loss of phase
coherency, due to the increasing number of multiple paths as distance from
the station increases.

"Goofball_star_dot_etal" wrote in message
...
On Wed, 22 Jun 2005 20:56:44 -0400, "Robert Morein"
wrote:


The twinlead
from a folded dipole is part of the antenna system itself. Therefore, it
picks up more signal, which can cancel with that received by the nominal
antenna.

********! (7)
It is a balanced transmission line which is matched to the balanced
300ohm folded dipole. The fields associated with the twin conductors
of the feeder cancel in the far field. It cannot radiate/recieve
itself if it is properly balanced.

The cancellation is not perfect, because the conductors are not coincident.
In the 60's and 70's, twinlead used as antenna feed was a major cause of
ghosting, which is a multipath related effect.

Your belief that the far field cancels is based upon the analysis of a
point-source dipole, which is merely a theoretical tool.

On Sun, 26 Jun 2005 17:04:04 -0400, "Robert Morein"
wrote:


"Goofball_star_dot_etal" wrote in message
...
On Wed, 22 Jun 2005 20:56:44 -0400, "Robert Morein"
wrote:


. Therefore, it
picks up more signal, which can cancel with that received by the nominal
antenna.

********! (7)
It is a balanced transmission line which is matched to the balanced
300ohm folded dipole. The fields associated with the twin conductors
of the feeder cancel in the far field. It cannot radiate/recieve
itself if it is properly balanced.

The cancellation is not perfect, because the conductors are not coincident.
In the 60's and 70's, twinlead used as antenna feed was a major cause of
ghosting, which is a multipath related effect.


LIke I said, plastering it into walls is not ideal. . .

"The twinlead from a folded dipole is part of the antenna system
itself." seems clear enough and wrong.

Your belief that the far field cancels is based upon the analysis of a
point-source dipole, which is merely a theoretical tool.


If it leaked it would be lossy. Coax is convienient.

On Sun, 26 Jun 2005 17:00:32 -0400, "Robert Morein"
wrote:


"Goofball_star_dot_etal" wrote in message
...
On Tue, 21 Jun 2005 02:38:10 -0400, "Robert Morein"
wrote:

There really isn't.
It is a common misconception that a station is not received due to
inadequate signal strength. This is actually quite rare.

******** (run out of fingers)

It is the rule that the vast majority of VHF stations are out of
range.

The range is usually not determined by signal strength. It is loss of phase
coherency, due to the increasing number of multiple paths as distance from
the station increases.


There is no doubt that multiple paths can mess up your TV or FM stereo
but there is also no doubt that signal decreases with range, rapidly
for VHF over ground and more rapidly when the path passes close to or
over the horizon. 40miles is a long way unless the antennae are high
up. High antenna gain is good whatever but at 88.3 MHz indoors that is
not really much of an option. Get the antenna out and UP if one can.

Goofball_star_dot_etal wrote:
On Sun, 26 Jun 2005 17:00:32 -0400, "Robert Morein"
wrote:


"Goofball_star_dot_etal" wrote
in message
...
On Tue, 21 Jun 2005 02:38:10 -0400, "Robert Morein"
wrote:

There really isn't.
It is a common misconception that a station is not
received due to
inadequate signal strength. This is actually quite
rare.

******** (run out of fingers)

It is the rule that the vast majority of VHF stations
are out of
range.

The range is usually not determined by signal strength.
It is loss
of phase coherency, due to the increasing number of
multiple paths
as distance from the station increases.

There is no doubt that multiple paths can mess up your TV
or FM stereo
but there is also no doubt that signal decreases with
range, rapidly
for VHF over ground and more rapidly when the path passes
close to or
over the horizon. 40miles is a long way unless the
antennae are high
up. High antenna gain is good whatever but at 88.3 MHz
indoors that is
not really much of an option. Get the antenna out and UP
if one can.

Agreed. Which is more important - strength of the signal or
purity of the signal is dependent on the specfic sitaution.

When I was a teen-ager I DXed the midwest from my a roof
antenna on my parent's house on the northeast side of
Detroit. There were multipath issues with some stations
downtown, but signal strength and propigation situations
limited my ability to pull stations out of mid-Ohio, etc.

My all-time DX record involved picking up stations in Miami
Florida from El Paso Tx, but this was one-time thing. Quite
clearly over the horizon.

I also picked up some stations in New Mexico, possibly by
means of a known means of popagation of VHF signal through
solid mountains.

I was generally able to distinguish audibly between stations
that were trashed by multipath, versus stations that were
trashed by low signal strength, versus stations that were
trashed by interferring signals.

On Sun, 26 Jun 2005 19:53:53 -0400, "Arny Krueger"
wrote:


Agreed. Which is more important - strength of the signal or
purity of the signal is dependent on the specfic sitaution.

When I was a teen-ager I DXed the midwest from my a roof
antenna on my parent's house on the northeast side of
Detroit. There were multipath issues with some stations
downtown, but signal strength and propigation situations
limited my ability to pull stations out of mid-Ohio, etc.

My all-time DX record involved picking up stations in Miami
Florida from El Paso Tx, but this was one-time thing. Quite
clearly over the horizon.


Sporadic -E possibly.

I also picked up some stations in New Mexico, possibly by
means of a known means of popagation of VHF signal through
solid mountains.

That's news to me.


I was generally able to distinguish audibly between stations
that were trashed by multipath, versus stations that were
trashed by low signal strength, versus stations that were
trashed by interferring signals.


You would have to rather unlucky to spend your life in a null but Bob
does not seem to be very lucky, Multipath is not an issue at sea but
the signal still disappears. NY might well be different. . .

On Sun, 26 Jun 2005 13:34:31 -0700, ric wrote:

Joseph Oberlander wrote:

Their marketing is rubbish, btw. Any standard "whip" type
antenna will work like that - just shorten it to the exact
frequency that you desire and aim it around until you get a
good signal.


A lower frequency requires a *shorter* antenna?? I thought it would
have to be *longer*. Please explain.

Sorry - I got it reversed. but the theory is the same - find
the right length and make it so. Then aim.

Sorry, but I am having trouble figuring out how to extend a whip
antenna to a length longer than its maximum. Hints?

Stick a saucepan lid on the end (capacitive loading) or a crock clip
with wire attached. The possibilities are endless.

Google "top hat" antenna

Goofball_star_dot_etal wrote:

Sorry, but I am having trouble figuring out how to extend a whip
antenna to a length longer than its maximum. Hints?

Stick a saucepan lid on the end (capacitive loading) or a crock clip
with wire attached. The possibilities are endless.

Would that be a steel or an aluminum saucepan lid?

On Mon, 27 Jun 2005 22:03:59 -0700, ric wrote:

Goofball_star_dot_etal wrote:

Sorry, but I am having trouble figuring out how to extend a whip
antenna to a length longer than its maximum. Hints?

Stick a saucepan lid on the end (capacitive loading) or a crock clip
with wire attached. The possibilities are endless.

Would that be a steel or an aluminum saucepan lid?

I don't think it matters. All the current is at the bottom end so the
resistance or non linear properties of steel will not have any
significant effect at the top end where the impedance is high. A
half-eaten can of baked beans or even wet cardboard might do. .
Getting a good connection and the right diameter is more of an issue.
I have little idea of the size required but if you have a telescopic
whip, make the "top hat" just large enough to be withinn the range of
adjustment. It may be difficult to notice any diffence without some
form of transmitter or reflected power meter but if you can't hear the
difference then it does not matter.

A preamp/rf amp may well help despite what you may have been told. In
and ideal world,with a good outdoor antenna, the signal to noise is at
these frequencies limited by the "sky" noise (sun etc.). Amplifying
both the signal and noise does not improve the ratio. With an indoor
antenna, however, both will have been attenuated by the fabric of the
buiding and the signal to noise will be determined by the radio front
end. This is unlikely to be up to the standards of a good preamp ie. a
Ham 4 metre preamp although this would probably need to be tweaked.
The potential disadvantage of a preamp is that the higher signal
levels in the mixer etc may lead to greater spurious responses and an
unpleasant background noise between channels (without a squelch
control). On the other hand, driving weak signals to limiting at the
IF should help FM demodulation performance.

ric wrote:

Joseph Oberlander wrote:


1/2 WL dipole length = 468/f = 468/88.3 = 5.3 feet = 63.6 inches.

Since none of the existing FM dipoles I have are 63.6 inches long (the
longest being just under 5 feet), should I assume that is why they are
so poor in the "college" (88-90 MHz) FM band?

Ah. you *can* get 6 fters. They are custom parts, though, and not
sold at Radio Shack and simmilar places.


Even the $25 "FM Select" dipole has only a 54" element. That's optimized
for 104 MHz. No thanks.

http://www.ccrane.com/fm-reflect-antenna.aspx

Try looking in CB supply stores and also marine equipment. These
ultra-long antennas are common on shortwave radios as well.

http://www.qsradio.com/QuickSticks.htm
96 inches should be long enough for any application.

On Tue, 28 Jun 2005 15:41:39 GMT, Joseph Oberlander
wrote:



ric wrote:

Joseph Oberlander wrote:


1/2 WL dipole length = 468/f = 468/88.3 = 5.3 feet = 63.6 inches.

Since none of the existing FM dipoles I have are 63.6 inches long (the
longest being just under 5 feet), should I assume that is why they are
so poor in the "college" (88-90 MHz) FM band?

Ah. you *can* get 6 fters. They are custom parts, though, and not
sold at Radio Shack and simmilar places.


Even the $25 "FM Select" dipole has only a 54" element. That's optimized
for 104 MHz. No thanks.

http://www.ccrane.com/fm-reflect-antenna.aspx

Try looking in CB supply stores and also marine equipment. These
ultra-long antennas are common on shortwave radios as well.

http://www.qsradio.com/QuickSticks.htm
96 inches should be long enough for any application.

Sigh. Size isn't everything.
Those are HF aerials with blobby things.

Goofball_star_dot_etal wrote:

Stick a saucepan lid on the end (capacitive loading) or a crock clip
with wire attached. The possibilities are endless.

Would that be a steel or an aluminum saucepan lid?

I don't think it matters. All the current is at the bottom end so the
resistance or non linear properties of steel will not have any
significant effect at the top end where the impedance is high. A
half-eaten can of baked beans or even wet cardboard might do. .

Hmmm...all that I have available is a 3/4 eaten can of lentel beans. I
would have to do the math, I suppose.

On Tue, 28 Jun 2005 13:36:55 -0700, ric wrote:

Goofball_star_dot_etal wrote:

Stick a saucepan lid on the end (capacitive loading) or a crock clip
with wire attached. The possibilities are endless.

Would that be a steel or an aluminum saucepan lid?

I don't think it matters. All the current is at the bottom end so the
resistance or non linear properties of steel will not have any
significant effect at the top end where the impedance is high. A
half-eaten can of baked beans or even wet cardboard might do. .

Hmmm...all that I have available is a 3/4 eaten can of lentel beans. I
would have to do the math, I suppose.

Go for it, forget the maths.
BTW 4 metres is a little used British only band, I have discovered.
Pity. I did find one preamp but it is not worth the expense on the off
chance it would help. http://www.microwave-modules.com/summary.html

Goofball_star_dot_etal wrote:

Hmmm...all that I have available is a 3/4 eaten can of lentel beans. I
would have to do the math, I suppose.

Go for it, forget the maths.
BTW 4 metres is a little used British only band, I have discovered.
Pity. I did find one preamp but it is not worth the expense on the off
chance it would help. http://www.microwave-modules.com/summary.html

ACK! All those prices in British Pounds. Will the conversion rate to
Euros affect my reception?