Alternate Antenna ideas?

I'm working on a 72 Duster project. The owner and I decided to shave the side marker holes along with the trunk lock. We're also adding in a flip top gas cap, set in to sit nearly flush. Now I'm considering filling in the stock antenna hole in the right fender. IF I do this, what are the options for an alternate antenna? GM cars used windshield antennas for years, which got me wondering if there were other places to hide one. Can one be fashioned BEHIND the windshield trim and still be functional? What about behind the grille? I'm looking for a way to have it hidden yet still provide decent reception.
Ideas, anyone?

Unless designed specifically without one, the antenna needs a ground plane to get good reception. Tim

Hey, I spell well but I certainly can't claim to understand everything! Care to explain what "Ground plane" means!!?

Cut & paste..

A Ground Plane is a flat surface of ferrous metal (galvanized, steel, etc) that a Magnet Mount or Body Mount antenna uses as an integrated part of it. For a Body mount antenna other metals may be used as it does not have a magnet that needs to stick to it.

A Metal Car Body is a ground plane.

The metal top of a refrigerator is a ground plane.

A filing cabinet is a good ground plane.

A tin roof is a Ground Plane.

A ground plane can be a cookie sheet!

A ground plane is NOT a metal roof gutter, a window frame, a downspout or any other piece of metal that is long and thin.

A ground plane MUST satisfy BOTH length and width dimensions outlined below. Antenna gains are calculated with an infinite ground plane. Performance can be achieved with the minimums outlined below.

Just as long as it is big enough:

for Dual Band/800 MHz/Nextel = 14" x 14" Minimum (28" x 28" recommended)

for 1900 MHz only = 6" x 6" minimum (12" x 12" recommended)

A Ground Plane does not need to be electrically grounded. It simply needs to be a plane of metal.

Your local hardware store sells galvanized roof flashing for cheap that can be used as a ground plane.

Please note, the antenna should be mounted in the CENTER of the ground plane for a circular pattern.




I've talked to many street rod owners with hidden antennas & none of them rave about the reception, they work but not very well... The ones that mount behind the windshield rather than in the headliner get better reception & the Hirschmann seems to be the best.... I wound up putting an amplified short (16" Hirschman Fuba) in the roof of my Falcon wagon since there was already a hole there from a CB antenna..

Grove Enterprises in Brasstown NC used to manufacture and sell an antenna that was embedded in a clear length of tape and could be attached to either front or back window,
but I just checked their online catalog and it is no longer there.
They might make one on special request:

http://www.grove-ent.com/widefrequencycoverageantennas.html

to avoid the ground plane requirement
you could make a simple FM band
'coaxial dipole'
antenna at the end of a length of coax and mount that
behind the grille,
at the top back window,
or below the rear bumper.
This would still pick up reasonably good AM band, maybe better than an standard 28 inch quarter wave 'Marconi' antenna.



http://en.wikipedia.org/wiki/Coaxial_antenna

my experience with alternative hidden vehicle antennas
was with a wide band antenna hidden underneath a ARE fiberglass tonneau bed cover on a Ram pickup... which worked great over a wide spread of frequencies.

The official FCC cars hunting un-licensed radio transmitters (Pirate FM) have four hidden antennas that are still very effective.

Years ago we had an antenna under a car; it ran lengthways, secured at its base and with a small clamp at its end to keep it tucked up. Reception was OK for the stronger stations but not as good as OEM.
The easy way out for you might be a power-retracting antenna, especially if it could be hidden in a body gap so that when it's retracted it disappears...

Quote:

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Grove Enterprises in Brasstown NC used to manufacture and sell an antenna that was embedded in a clear length of tape and could be attached to either front or back window,
but I just checked their online catalog and it is no longer there.
They might make one on special request:

http://www.grove-ent.com/widefrequencycoverageantennas.html

to avoid the ground plane requirement
you could make a simple FM band
'coaxial dipole'
antenna at the end of a length of coax and mount that
behind the grille,
at the top back window,
or below the rear bumper.
This would still pick up reasonably good AM band, maybe better than an standard 28 inch quarter wave 'Marconi' antenna.



http://en.wikipedia.org/wiki/Coaxial_antenna

my experience with alternative hidden vehicle antennas
was with a wide band antenna hidden underneath a ARE fiberglass tonneau bed cover on a Ram pickup... which worked great over a wide spread of frequencies.

The official FCC cars hunting un-licensed radio transmitters (Pirate FM) have four hidden antennas that are still very effective.

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To see what you are up against for AM radio, the diagram shows the antenna rod to be 1/4 wavelength. At 850khz in the middle of the AM band, 1/4 wavelenghth is 290 feet! That is why AM radios in cars were usually more sensitive but still did not hear terribly well, buzzed under powerlines, etc. Windshield antennas worked even worse, so much so, the National Association of Broadcasters wanted them banned from new car manufacturing at one time.
All AM antennas on a car are a compromise. A windshield antenna is a worse compromise since it will be directional, favoring where the car is pointed and shielded on three sides.
FM is another story, 1/4 is about 30 inches, the length of the non adjustable antennas on 70s Mopars and most cars with fender mounted antennas today. It is much easier to hide an FM antenna and while the windshield is not ideal, it will work better than AM
Craig