It doesn't take much. Back in the early '90s a group of us were returning
from a hamfest and I was riding in the back seat of one guy's late '80s
Ford something or other (Crown Victoria, maybe?). I was using my HT to
talk to the other car on 2m and the driver noticed that his cruise control
was gaining speed and when I unkeyed it settled down. Once I figured out
it was my HT causing it, loads of fun ensued.

If something is sensitive to RF, it probably won't take much to cause it
to malfunction. The fact is that nobody does RF shielding or protection
for consumer electronics, so there is no set power limit below which a
device may not be affected.

- Nate

--

"The optimist proclaims that we live in the best of all possible worlds,
the pessimist fears this is true."

On Feb 12, 4:40 pm, Nate Bargmann
wrote:
It doesn't take much. Back in the early '90s a group of us were returning
from a hamfest and I was riding in the back seat of one guy's late '80s
Ford something or other (Crown Victoria, maybe?). I was using my HT to

If something is sensitive to RF, it probably won't take much to cause it
to malfunction. The fact is that nobody does RF shielding or protection
for consumer electronics, so there is no set power limit below which a
device may not be affected.


The increased prevalence of EMI/EMC problems means that modern cars
are MUCH better about this. Almost all new cars go through a fairly
rigorous test program for immunity from radiated fields. Nobody wants
to have the engine or braking control systems fail when the police car
next to them calls home on their VHF low band radio. There's rafts of
SAE specs for this, but I don't recall the field strengths. Several
hundred volts/m though, is what I think.

Aftermarket addons (stereos, nav systems, etc.) aren't nearly as good
on the account. Some automotive equipment is exempt from Part 15 (for
instance, the nifty OBD II readers are pretty good RFI emitters...)

"Nate Bargmann" wrote in message

If something is sensitive to RF, it probably won't take much to cause it
to malfunction.


True. One time I was testing VHF antennas at 5 watts output in a quiet
garage. I kept hearing a clicking noise every time I keyed up. I traced
it to an analog multimeter on my bench. I was pegging the poor meter from
about ten feet away.

I installed an Icom 2000 into my Commodore, a 92 VP sedan with a V6 engine,
and everytime I keyed the mike at full TX power the engine would stall,
whether at idle or on the road, very disconcerting!
I cured the problem by re-routing the coaxial cable away from the computer.
VK2KCE

"Nate Bargmann" wrote in message
et...
: It doesn't take much. Back in the early '90s a group of us were returning
: from a hamfest and I was riding in the back seat of one guy's late '80s
: Ford something or other (Crown Victoria, maybe?). I was using my HT to
: talk to the other car on 2m and the driver noticed that his cruise control
: was gaining speed and when I unkeyed it settled down. Once I figured out
: it was my HT causing it, loads of fun ensued.
:
: If something is sensitive to RF, it probably won't take much to cause it
: to malfunction. The fact is that nobody does RF shielding or protection
: for consumer electronics, so there is no set power limit below which a
: device may not be affected.
:
: - Nate
:
: --
:
: "The optimist proclaims that we live in the best of all possible worlds,
: the pessimist fears this is true."