This is what Holland posted a while back....

-----Original Message-----
From:	Holland J. Phillips [SMTP:phillip3@apple]
Sent:	Tuesday, October 07, 1997 11:53 AM
To:	MVenture88@aol; gtivr6_dallas@hotmail;
owner-gti-vr6@dev.tivoli; GTI VR6 List; DFutrell@whpacific
Subject:	Fuba's the final word - from me

Ok, here's MY final word on this thread:  
The Fuba antenna on the GTI/GLX cars is an amplified antenna which 
requires DC electrical power from somewhere.  On the non-Fuba cars,
they 
use a standard passive antenna, which gets it's gain (amplification)
from 
it's length, hence, the Fuba is less than 17" long, and most standard 
(passive) FM antenna's are 29-31" long, which is about a quarter wave 
length of the FM band (87-107 MHz).  In antenna theory, antennae that
are 
certain fractions of a given wave length (1/4, 1/2, 5/8, 3/4, as well
as 
a whole wave length) in length, will resonate at that corresponding 
frequency, hence providing an increase in the signal (voltage) produced 
by antenna, which provides the front end of the receiver with an 
amplifiable input.  The Fuba does the same thing using a powered 
amplifier, so a much shorter antenna mast will work.  This is why VW
uses 
the same head/receiver unit for both amplified and non-amplified 
antennae.  This also explains why the Fuba equipped cars don't pick up 
didley without the power lead to the antenna connected.

'nuff said,

Holland

---Bruce Foss <BFoss@media100> wrote:
>
> I got a new stereo put in.  They did put in a metal tube behind thehead
> unit relating to the 12V antenna (this is where my memory fails me-
> exactly how the antenna is powered).  Without it, they said the radio
> got NO reception.  With it, I get FM decently, and AM not at all.
> 
> Does anybody have this information about the antenna?  I know Iclipped
> it a while ago but must have lost it.
> 
> Thanks,
> 
> 
> Bruce