The AM Forum

I have a 2008 Acura and commute about 90 miles a day. Tonight on the way home I was listening to a weak AM station- I usually listen to a local 50K watt station when on AM
Long story short I found that when my left front tire passed over a white line on I-091 there was a pretty loud static when I was going over the white strip. I must have looked like a drunk as I tried all tires weaving back and forth. There were areas where the paint seemed older and it did not do it but once I hit a fairly new place it came back.
This was on 91 SB in CT North and South of Hartford. Also noticed it on Rte 9 SB
Must be something in that reflective paint.
Carl
/KPD

Does your Acura have a TPM (tire pressure monitor)? The wheels usually have sensors mounted in them. Could possibly have somehting to do with it.

Phil

It does have TPM. But the effect is only in the one wheel....

It's real simple. There are smart chips impregnated in the strips that were communicating with the command module in you cars CPU telling the federalists where you are as you travel along. Be careful!!!   

Good thing I have my aluminum foil hat and underwear on when I drive....

Here's where I show my age... :)
I remember back in the day that the grease caps on front wheels had spiral wound springs in them to ground out the wheel to the spindle. Reason being that when up to speed the hydraulic wedge of grease between the bearings and races insulated the wheel and static built up to undesirable levels. 

Sounds like them ol' timers knew something that's been fergot.  But it makes sense to me that you may have one set of wheel bearings that weren't overtightened (as they frequently are these days, but that's another rant) and that one wheel is building up static on the insulated stripe.

??: How do you know it's just the front tire? At highway speed don't they pretty much follow the same track? I'm assuming it's front wheel drive, in which case only the rear wheels would be floating on spindles.

For academic purposes I'd jack 'er up and spin the wheels with an ohmeter from the center of the grease cap to chassis and see if I lose continuity.  Of course, I have been accused of being a few fries short of a Happy Meal too.

No good on that one. The bearings are pressed onto the hub on that ride. Just a thought; swap the two front tires and give it another try. Could be a loose ground strap somewhere on the LF of the vehicle or rusted fasteners for said possible gnd. strap. I have heard tales of U-joints and bearings going bad prematurely because a chassis ground strap left off or loose or such and battery ground returned through the drivetrain instead.

Phil 

Speaking of age, I recall some powder that was added to the inner tube that would stop this kind of static.  Been a long time so I bet you will have a tought time finding a packet and an inner tube.  You do know what an inner tube is, don't you?  :>)

Having worked in a garage I remember the spring in the greese cap and the magic powder.
Carl, stay in your lane and there will be no problems. I saw the hawk yesterday. He was flying over my head while I was taking my walk.
He must have thought, what a juicy one if I could haul him home

OK Phil,
I wasn't sure what you meant by the bearings being pressed in to the hub. Aren't they all? So I found an image of the rear hub for a 2008 Accura and yes, the outer races are pressed in to the hub as usual, but the bearing rollers and inner races are still potentially insulated by two layers of grease when spinning.
Spindle-inner race-grease-rollers-grease-outer race-hub.
So I'll stick by my hypothesis for the time being, unless I missed something.

Didn't know their was a powder to distribute a charge inside the inner tube. Could it have been graphite?

I've have heard about drive trains getting chewed up by ground returning to the engine block through the rear end when a body strap got left off. Seems to have been most common on trucks with rubber mounted bodies on girder chassis.

Neat stuff!

Reflective paint used to be made with glass beads to give the reflective property...

Maybe they're using aluminum or some other such thing now?

They still use glass beads in road paint, at least here in CT they do.

I remember back in the 60's there was a particular intersection where a strong tunable hum appeared on whatever AM BC station I was listening to when I passed through it.  At the intersection, there was a trip light, that was activated whenever a car passed over a plate in the street, and turned the light green.  If you had a motorcycle or other light vehicle that would not activate the  light, or somehow you failed to trip it, your only alternative was to run the red  light.  There was a no right turn on red law in effect in those days. It never happened to me, but I suspect in a lot of places tickets from running those red trip lights were good revenue generators. I never was able to figure out how the trip light induced tunable hum on  the radio.

Regarding stripes on the road, rumble strips at the edge of the pavement on both sides of the road have saved countless lives. They should be mandatory on all rural highways.

Interesting phenomenon Carl. I make the trip from East Granby down to Clinton a couple times a month and have never encountered that. I usually listen to 1080 and then 880 along Route 9 but have never heard static when veering around all the farmers driving their pickup trucks loaded with chickens.

I wonder if it could be the Chinese paint that the CT DOT switched to. There is some metallic residue mixed in with the paint. Probably from spent fuel rods...

Rob has a good point! Which is funny, but, at the same time a little scary! The Chinese so seem to be perfectly fine with whatever they decide to ship out of their country. We ran a few 200LC's with Chinese built mainframes a few years back; obviously ratty welds throughout, crummy hardware, etc. I could just casually look it over and tell whether it was imported or built in-house.

As for roadside RFI, check out flashing work signs, new hi intensity  multi-LED traffic lights, most all gas stations. There are probably quite a few more that I missed.

Ahhh, the old days! Breaker point ignition, cannister style oil filters, bias-ply tires with inner tubes, and tweaky carburetors. You just didn't know for sure when you went out in the morning to start up the car if it was going to run that day or not. Where have all the good times gone? I still have my Chevelle, but it's more or less a lawn ornament at this point. 

Phil

Its the material.   Way out on I-10 on the way to California, There is a paint test area.  In the left lane, There are about 10 to 15 white and yellow strips across the lane.  They put it there and let cars run over it for a time period, Then go out and see which type of paint wears out faster or which one keeps the reflective material.  Some are clearly gone now. Some are there nice and bright. 

As I pass over this section,  My radio makes a loud interferance sound.

C

"spent fuel rods"....more truth to that than poetry.......Tin foil underwear is a must these days

It will be interesting. I had the car in the shop Friday and they had to replace a bad wheel bearing, I have not had a chance to ride over the all areas where I know it happened but will do so on Monday. I went over a couple of small sections of another road and it seemed to OK but have not given it the real test

It has to be this - I checked with General Motors...

Mike WU2D

http://www.youtube.com/watch?v=oIS5n9Oyzsc

No mention of the framistat used in the entabulator.  That could be the cause of the static.

Maybe you should check the rubber strap under the car that drags on the ground..........anyone remember that? It was to reduce static electricity.
Showing my age here
Fred

I still see vehicles with that strap and I dont mean just dynamite carriers and fuel trucks.

Carl
KM1H