On Tue, 13 Feb 2007 00:24:38 -0500, Chuck Reti
wrote:

In article .com,
"KE5MBX" wrote:

Hi,
What's all this business I hear people talking about blasting people's
car stereos or killing cars altogether with high-power RF? I run 2m,
10m, and 11m in my jeep and I'd like to sort out the fact from the
legend and find out what kind of power I can use without risking
damage to my jeep or cars around me. At what power level is front-end
overload to a nearby radio likely? At what power level is damage
likely, and to what componets?

I am currently using only 50 watts on a 5/8 wave (2m), 25w on a 1/4
wave (10m), legal 4w on a 1/4 wave (11m)

Thanks,
Nelson KE5MBX

A few years ago. while in freeway traffic, my Chrysler minivan suddenly
kicked into "limp" mode (no response, low rpm, second gear only), as a
CB-er in a large van passed next to me. He had one of those stupid fat
antennas with the gigantic "loading coil," and had to have been running

You are not describing a CB antenna.

a few KW for the Good Buddies.
The auto companies are well aware of the havoc RFI/EMI can wreak on a
vehicle's microprocessor-based control systems for engine, drivetrain,
braking,etc., not to mention the entertainment and navigation systems.

And Chrysler had a V-6 (I was going to purchase one) that ran the
computer on 147.00. One of those would drowned out the local repeater
that was only 2 miles away from a distance of nearly 3/4 of a city
block. I worked with the local dealer for several weeks, but we could
not get Chrysler to even admit to a problem.

I once had the opportunity to see the RF testing lab at the tech center
of one of the "Big 3." It was a pretty impressive array of equipment and
testing environments, and they try to anticipate and head off "worst
case" problems.

ARRL has some good info on the subject:
http://www.arrl.org/tis/info/carproblems.html

Actually, due to Chrysler's refusal to even talk about the matter I
ended up with a Toyota 4-Runner and I run one whale of a lot more than
100 watts even on 2-meters.

To top it off the Toyota mechanics ran the wiring for me, so all I had
to do was plug in the radios, stick on the antennas and go.
Currently I just have the 50 watt TM-D700 (35 watts on 440) and a 160
watt out Mirage amp on 144. It runs closer to 180 watts on the Bird
watt meter. I also have the Yaesu FT-897D, but I'm presently using it
in my shop as a back up rig. When back in the car that will be capable
of running about 600 watts out.

Chuck WV8A Detroit MI
Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com