[RFI] Auto quieting

Roger (K8RI) k8ri at rogerhalstead.com
Thu Oct 8 04:06:20 EDT 2015

Why not just use RG8 type coax for the 12 VDC wiring?  I'd use separate 
cables for +/- instead of using the shield for the negative return. 
Color code the cables at each end with colored tape.  Run the cables 
together.  Use double shield for good measure.  Yes they take up more 
space, but I've had good luck with it in the past.  Use a relay to shut 
off the rig when the car is shut off.  It does have drawbacks, but at 
least you won't run the battery dead if you forget to turn the rig off.

Both our cars have computers, ABS brakes, and my wife's car is a hybrid 
with well over 100,000 miles on it.  Other than following good practice 
we took no special precautions.  All this RFI talk has me afraid to 
purchase a newer car as it's getting about time as the maintenance costs 
are rising on the old 4-Runner.  I can't convince my wife we need 
something with a lot of HP, but my old TA with the Corvette engine saved 
my life several times, even if it did make the ultimate sacrifice the 
last time.  OTOH, I drove more miles in a month back then than I do in a 
year now.

It's the thought of having to RFI proof a new car causing me to hold 
off.  Still. I can try them out and listen before buying.  If noisy, 
I'll pass.

One class X-10 CME direct hit and the cars will be RFI quiet!


Roger  (K8RI)

  On 10/5/2015 11:51 AM, Michael Coslo wrote:
> I used  old RG8 Coax shield - removed from the coax of course. Solder lugs on each end, and some heat shrink to keep it pretty. That will probably help with Kurt’s wire fraying issue too.
> One odd thing, K0BG discounts the idea of much RFI coming from injectors.  Good site though.
> I’m going to look at putting some coax shield over the injector wires, and ground at both ends. Maybe that will help my problem.
> -73 de Mike N3LI -
>> On Oct 5, 2015, at 1:16 AM, Mike Ryan <mryan001 at tampabay.rr.com> wrote:
>> I would suggest you taking a look at K0BG's website. He has about everything you could ask for with respect to mobile ops, from the types of car battery, to mobile antennas, grounding and bonding, etc.  It is a fantastic website with years of experience noted there. In my case I use inch wide tinned copper strap which cut to lengths as required. I think you would find the flat strap superior to round wire due to the additional surface area they provide.  - Mike
>> -----Original Message----- From: KD7JYK DM09
>> Sent: Sunday, October 04, 2015 11:53 PM
>> To: rfi at contesting.com
>> Subject: Re: [RFI] Auto quieting
>> "I had noise generated by the disc brakes on my car. When the static level
>> builds up (frequently) I step on the brakes and it cuts off like a switch.
>> It does not immediately come back but soon does."
>> I had this problem with static generated by the tires on the road arcing
>> over to the drive-line components.
>> I had another problem with massive static charges on a vehicle, I've been
>> thinking of the static wicks used on air-craft should this happen again.
>> Regarding bonding, which is better, flat woven strap or round cable/wire?  I
>> see everyone mention flat straps, but why?  I used them on a Toyota Celica
>> where I operated 6m/2m440 MHz, worked fine.  I sold the car to the OM up the
>> street, he came by one day, popped the hood and I noticed all the flat
>> straps had shattered in various places due to vehicle vibration.  Every
>> single strap was broken, wire pieces were all over the engine and components
>> and the straps were like cactus.
>> I've been eyeballing the various high-current ultra-flexible silicone and
>> XLPE covered welding wires at a local shop, they also have dozens of copper
>> connections in various shapes and sizes, thinking of using these when the
>> time comes.
>> Kurt
>> _______________________________________________
>> RFI mailing list
>> RFI at contesting.com
>> http://lists.contesting.com/mailman/listinfo/rfi
>> _______________________________________________
>> RFI mailing list
>> RFI at contesting.com
>> http://lists.contesting.com/mailman/listinfo/rfi
> _______________________________________________
> RFI mailing list
> RFI at contesting.com
> http://lists.contesting.com/mailman/listinfo/rfi

This email has been checked for viruses by Avast antivirus software.

More information about the RFI mailing list