Car antennas

[A. Joseph Ross]

Having recently been car shopping, I've noticed that radio antennas 
have changed again.   My old car had a retractible whip antenna that 
went up when the radio was turned on and down when it was turned off. 
 I had to replace that once in the life of the car, and it was 
already not going down all the way again.

I notice that a lot of newer cars have a small antenna, about six to 
twelve inches, above the rear window.  I wondered whether that would 
be sufficient for decent reception of AM and FM stations, but when I 
tested this on cars that I test-drove, it seemed to work.  Why is 
this antenna adequate?  Will it also work for satellite radio?

Other cars have an antenna embedded in the rear window.  I had a 1977 
Oldsmobile that had the antenna embedded in the front windshield.  I 
suppose embedding it in the rear window is about the same thing.  The 
antenna looks like a typical FM dipole.  Why does this work for AM as 
well, as it does seem to?

-- 
A. Joseph Ross, J.D.                           617.367.0468
 92 State Street, Suite 700                   Fax 617.507.7856
Boston, MA 02109-2004           	         http://www.attorneyross.com