Car radios

[Dan Strassberg]

I think a better reason for moving the ECU to the passenger side of the
firewall is to lower the temperature. High temperatures are the enemy of
semiconductor longevity. The engine compartment is shielded on five
sides--and on a few cars, six. My car (a 2002 Chevy Prizm, which is
generally identical to a 2002 Toyota Corolla) has a conventional
(non-retractable) whip antenna on the passenger-side fender--as far away
from the car's electrical-noise sources as it could be located. The 2002
Corolla has the (retractable) antenna on the driver's side A pillar, quite
close to the noise sources.

Now, I assume that the Chevy radio is made by Delphi (formerly Delco). I
have no idea who makes Toyota radios, but obviously whatever company does
was less concerned about antenna placement--at least until 2003. There are
no 2003 Prizms, but there is a 2003 Pontiac Vibe, also a Corolla derivative
and also made for GM by NUMMI (which is owned jointly by GM and Toyota). I
have no idea of the antenna location on the Vibe but I know that the 2003
Corolla antenna (and I think the antenna on the 2003 Toyota Matrix, which is
essentially the same as the Vibe) is located on the roof above the center of
the rear window. In 2003, Toyota started using short non-retractable
antennas on Corollas (and maybe other lines). I don't know whether the
radios compensate for the reduced antenna length with greater front-end gain
or whether the antenna uses some non-obvious technology to achieve the same
gain as would be obtained from a longer whip of conventional design. Can
anyone on the list tell me?

--
Dan Strassberg, dan.strassberg@att.net
eFax 707-215-6367

----- Original Message -----
From: SteveOrdinetz <steveord@bit-net.com>
To: <boston-radio-interest@bostonradio.org>
Sent: Friday, January 02, 2004 4:56 PM
Subject: RE: Car radios


> Bill O'Neill wrote:
>
> >Did this have anything to do with early-on interference with the on-board
> >computer systems?  Seemed plausible that moving the antenna away from the
> >engine
> >could help.
>
> Could be...it seems that a lot of cars that still use external whip
> antennas have them mounted on a rear fender.  I also wonder if that's why
> many cars have the ECU in the passenger compartment (on mine it's behind
> the glove compartment)...this way the car body itself acts as a shield.
>