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WHEEL STATIC ONLY ON SOME PATCHES OF PAVEMENT? WHY?
WHEEL STATIC ONLY ON SOME PATCHES OF PAVEMENT? WHY?
With the financial mess, I have started to listen to AM radio in the car on the way to and from work for the past few weeks and I've noticed some random static at certain locations. At first I attributed this to some power line noise. Bit it didn't really sound like 60 Hz buzz hash, it was more random popcorn like but I know power lines can blow around in the wind and have strange discharges so I didn't think too much of it for a while. But after a few days I noticed that the static is there only when the car is moving. OK, so its wheel static. Static electricity from the wheels or brakes or something. OK that's not unusual either. But it is the combination that has me curious. This static only occurs when the car is moving and it only occurs at certain repeatable locations on my drive. Everyday when I turn the corner from X to Y, I get the static as the car is moving, but not when stopped at the same corner. And I never get the static when turning the corner from A to B. If it was power line, stopping the car wouldn't stop the static. If it is wheel static, why does it not happen all the time and happen only at certain locations. It seems as if these certain locations have something special about the pavement or the water content of the soil or something. None of that seems likely to me though, I see nothing changing in the pavement as I drive from an area of static to an area of non-static. It is not related to stepping on the brake or gas or shifting gears or going over bumps or any other aspect of the car that I can tell other than it's speed down the road. As an experiment, I attached a drag wire under the car. The wire drags on the ground to discharge any static build up the car. This made no difference. Another clue, we've had no rain here in a while. The static all stops during wet weather. Also I am in the Philadelphia area and the AM station is in the New York area so it is on the weak side. I've been a ham for over 30 years and I have a lot of experience with EMI, but this one has me scratching my head. The wheel static changes repeatably in different locations for no apparent reason. It's got to be something to do with the pavement. Anybody have any experience with this? Mark |
WHEEL STATIC ONLY ON SOME PATCHES OF PAVEMENT? WHY?
On Wed, 5 Nov 2008, Mark wrote:
I've been a ham for over 30 years and I have a lot of experience with EMI, but this one has me scratching my head. The wheel static changes repeatably in different locations for no apparent reason. It's got to be something to do with the pavement. Anybody have any experience with this? Mark My guess is different lengths/types/orientation of rebar in the roadbed. -- My mailbox is NOT an advertisement medium. Tehrasha Darkon My address is NOT for sale, lease or rent. Send me spam, lose your account. Get it? TINLC-1372 http://tehrasha.mamehost.com/******* B.A.S.T.A.R.D |
WHEEL STATIC ONLY ON SOME PATCHES OF PAVEMENT? WHY?
"Tehrasha Darkon" wrote in message ... On Wed, 5 Nov 2008, Mark wrote: I've been a ham for over 30 years and I have a lot of experience with EMI, but this one has me scratching my head. The wheel static changes repeatably in different locations for no apparent reason. It's got to be something to do with the pavement. Anybody have any experience with this? Mark My guess is different lengths/types/orientation of rebar in the roadbed. -- My mailbox is NOT an advertisement medium. Tehrasha Darkon My address is NOT for sale, lease or rent. Send me spam, lose your account. Get it? TINLC-1372 http://tehrasha.mamehost.com/******* B.A.S.T.A.R.D ------------ Or electronic/magnetic sensors embedded in the road. Ed, NM2K |
WHEEL STATIC ONLY ON SOME PATCHES OF PAVEMENT? WHY?
Hi Mark
I'll admit I have never actually noticed it but your experience sounds plausible. So me thinking in fundamental terms. - The ground strap not working implies a charge and discharge cycle in the wheel/axle. - When you corner the tyre/road, tyre/wheel, wheel/axle conductivity (or insulation properties) changes. - When the road surface changes physical or conductive properties also change. - Wet weather mixes wth the road dirt and produces are better conductive path and thus less of a voltage to discharge. Does applying the brakes (better conductivity hub/disc to axle/car) change or reduce the noise? (It will also distort the tyre shape in a like mannner to cornering so this test may be invalidated. Try just making the pads bind slightly with the drum/disc so it doesnt affect tyre shape) Does driving on a noisy stretch with a wheel on the lane marking paint yield slightly less noise? (Wow, a new way to measure road speed!) If this gets to be a positive test you can try one side or the other to see if it is wheel dependent. (The kerb side tyres will of course have slightly more surface on the road due to road camber,) Hard to test but does the noise stop straight away on wet pavement or does the water have to take some time to get well ingrained onto the tread and side surfaces of the tyre? The more tyre surface that is on the road (eg smooth pavement, cornering G or wet pavement) the more likely the static charge will discharge at a lower voltage (ie less noisy) Can you make the problem worse by adding some more air to your tyres? Road material conductivity to the underlying "ground" I dont think would be that significant but I'll admit I have never measured it. I would have thought that it is low enough resistance (including any rebar!) to not be factored in. I am prepared to be shot down over this though! Interesting/Intriguing situation! You can of course just try some of that conductive powder that goes inside the tyre. Something like that green roadside puncture repair stuff may also help and additionally give you some protection for its priamry use! Please get back to us with what you find. Cheers Bob VK2YQA/W5 East Texas (It is too dangerous for me to use AR in the car nowadays. I am so use to veering the "wrong way" from driving for so long on the other side I cant afford the risk! Sigh! - Yeah I also spell "tyre" the other way!) Mark wrote: WHEEL STATIC ONLY ON SOME PATCHES OF PAVEMENT? WHY? |
WHEEL STATIC ONLY ON SOME PATCHES OF PAVEMENT? WHY?
On Wed, 5 Nov 2008 17:36:26 -0800 (PST), Mark
wrote: WHEEL STATIC ONLY ON SOME PATCHES OF PAVEMENT? WHY? With the financial mess, I have started to listen to AM radio in the car on the way to and from work for the past few weeks and I've noticed some random static at certain locations. At first I attributed this to some power line noise. Bit it didn't really sound like 60 Hz buzz hash, it was more random popcorn like but I know power lines can blow around in the wind and have strange discharges so I didn't think too much of it for a while. But after a few days I noticed that the static is there only when the car is moving. OK, so its wheel static. Static electricity from the wheels or brakes or something. OK that's not unusual either. But it is the combination that has me curious. This static only occurs when the car is moving and it only occurs at certain repeatable locations on my drive. Everyday when I turn the corner from X to Y, I get the static as the car is moving, but not when stopped at the same corner. And I never get the static when turning the corner from A to B. If it was power line, stopping the car wouldn't stop the static. If it is wheel static, why does it not happen all the time and happen only at certain locations. Question: you say the static only occurs when the car is moving and gave two scenarios where the car is moving: turning the corner from X to Y (with static) and A to B (no static). My first question is are these right turns, left turns or one of each? Is there a traffic light at one and not at the other? Do you hear the static when driving straight or performing the turns in other locations? Two theories he 1)is that maybe when you turn, something is coming into contact with something else completing a circuit (or alternately seperating and breaking a circuit) that would result in your static and 2) if turn X to Y and A to B are at different intersections, there might be something in the environment at the X to Y intersection that may not be present at the A to B intersection - such as a traffic light and its sensors and controllers, a business's sign etc... My second question is have you tried the static producing maneuver with the radio turned off? Just curious as to if the source of the noise is from the sound system or maybe from another source that you may not have noticed before you started listening to the AM radio - car bodies and panels can flex some when under g loads like turns and that could be the source of your noise. -- "I... Can't drive... FIFTY-FIVE!!" --Sammy Hagar |
WHEEL STATIC ONLY ON SOME PATCHES OF PAVEMENT? WHY?
On Wed, 5 Nov 2008 17:36:26 -0800 (PST), Mark
wrote: WHEEL STATIC ONLY ON SOME PATCHES OF PAVEMENT? WHY? With the financial mess, I have started to listen to AM radio in the car on the way to and from work for the past few weeks and I've noticed some random static at certain locations. At first I attributed this to some power line noise. Bit it didn't really sound like 60 Hz buzz hash, it was more random popcorn like but I know power lines can blow around in the wind and have strange discharges so I didn't think too much of it for a while. But after a few days I noticed that the static is there only when the car is moving. OK, so its wheel static. Static electricity from the wheels or brakes or something. OK that's not unusual either. But it is the combination that has me curious. This static only occurs when the car is moving and it only occurs at certain repeatable locations on my drive. Everyday when I turn the corner from X to Y, I get the static as the car is moving, but not when stopped at the same corner. And I never get the static when turning the corner from A to B. If it was power line, stopping the car wouldn't stop the static. If it is wheel static, why does it not happen all the time and happen only at certain locations. It seems as if these certain locations have something special about the pavement or the water content of the soil or something. None of that seems likely to me though, I see nothing changing in the pavement as I drive from an area of static to an area of non-static. It is not related to stepping on the brake or gas or shifting gears or going over bumps or any other aspect of the car that I can tell other than it's speed down the road. As an experiment, I attached a drag wire under the car. The wire drags on the ground to discharge any static build up the car. This made no difference. Another clue, we've had no rain here in a while. The static all stops during wet weather. Also I am in the Philadelphia area and the AM station is in the New York area so it is on the weak side. I've been a ham for over 30 years and I have a lot of experience with EMI, but this one has me scratching my head. The wheel static changes repeatably in different locations for no apparent reason. It's got to be something to do with the pavement. Anybody have any experience with this? Mark So get yourself a decent portable AM radio. Use it instead and if you still hear the same static at the same locations, then you'll know it's not the car. My assumption is that it is the wiring in the car. Like a broken ground wire near the wheel well or even corroded wires. You can also buy filters which are generally capacitors that can be installed before the radio. I remember reading some time ago where some gal had this constant noise not in her car radio, but her teeth! She tracked the source down and found it to be a local radio station she was always passing. Now me personally, I can never figure this one out. Most of the time, when ever I go to bed, I'll hear a radio station. It's just enough to be annoying. I can rarely tell what's being said or played. I only hear it when I'm laying down on the bed, not sitting up. So I figure it has to do with the springs. |
WHEEL STATIC ONLY ON SOME PATCHES OF PAVEMENT? WHY?
Mark wrote:
"Wheel static only on some patches of pavement?" Why any wheel static ever? Springs used to be installed in hubs to make a sliding contact between the axle and the wheel. They must still be available. Graphite can be added to axle grease as is usual with speedometer cable lubrication. Graphite is powdered carbon and conductive. Best regards, Richard Harrison, KB5WZI |
WHEEL STATIC ONLY ON SOME PATCHES OF PAVEMENT? WHY?
Richard wrote:
"She tracked the source down and found it to be a local fadio station she was always passing." We contracted a crew boat in S. Louisiana from Nolan Duet (Doo A`). Nolan bought his wife a new car but she complained it made a clicking sound as she turned corners. Nolan told her she would just have to take the car back to the dealer. Nolan said: "I wasn`t going to tell that woman that it was the buttons on her dress that caused the noise!" Best regards, Richard Harrison, KB5WZI |
WHEEL STATIC ONLY ON SOME PATCHES OF PAVEMENT? WHY?
In article ,
Tehrasha Darkon wrote: On Wed, 5 Nov 2008, Mark wrote: I've been a ham for over 30 years and I have a lot of experience with EMI, but this one has me scratching my head. The wheel static changes repeatably in different locations for no apparent reason. It's got to be something to do with the pavement. Anybody have any experience with this? Mark My guess is different lengths/types/orientation of rebar in the roadbed. for a while glassfault i spelled it wrong it was asfault pavement that was made with recycled glass we did a test here in nyc i belive the first to do such testing and it was very conductive, caused a lot of problems with the testing gear so they put metal scraps in the mix didn't help we paved a 1/2 block test road initially and if you had the radio on and drove over it you heard a clearly different background noise ie higher ultimately the fixed it forgot how i think they tumbled the glass and added some chemical dunno if this has anything to do w/your specific case but anything from hitting a certain frequency vibration that causes a lose wire to rattle to perhaps some crappy wires burred under the st see any manhole covers around?? telco or sewers? typically they all have some juice and often make a bit of noise |
WHEEL STATIC ONLY ON SOME PATCHES OF PAVEMENT? WHY?
Hello Mark,
I used to drive a semi trailer years back, and had the same problem. It occurred only in fine hot weather, and the static build up used to wipe out 80m mobiling, plus the Am receiver on the broadcast band. It was what I call "Tyre Static" I noticed that in wet or damp weather it didn't occur, so I cured the problem by simply introducing some graphite powder into the grease of the outer wheel bearing on the front axle. Later on I found that a molybdenum based greases did the same job, without the mess of handling the graphite powder. I also found that steel belted radials were the culprit, but the early rayon biased tyres didn't suffer from the static build up problem at all. Main problem was that the rayon biased tyres didn't have the speed or load ratings the steel belted tyres have. A big problem is that nowadays with the introduction of sealed wheel bearings and front wheel drive vehicles makes it nigh impossible to introduce graphite powder or to re-grease the wheel bearings. By experimentation I found another cure, that was to put some graphite powder inside of the tyre before mounting the tyre on the rim (wheel), that reduces it as well. One can let the air out of the tyre and introduce graphite powder through the valve stem and then re-inflate the tyre. I found that the graphite powder inside of the tyre did not affect the at all, we used to recap our truck tyres up to 3 times, only thing was the tyre fitters hated dealing with the graphite inside of the tyre. On another problem not really related to highway use is that when farm tractors were fitted with UHF CB, ploughing in a paddock, static noise used to build up to a point where communication were impossible even over a short distance. The cure was to wipe the antenna down with a dry cloth. Hope this helps HarryH "Mark" wrote in message ... WHEEL STATIC ONLY ON SOME PATCHES OF PAVEMENT? WHY? With the financial mess, I have started to listen to AM radio in the car on the way to and from work for the past few weeks and I've noticed some random static at certain locations. At first I attributed this to some power line noise. Bit it didn't really sound like 60 Hz buzz hash, it was more random popcorn like but I know power lines can blow around in the wind and have strange discharges so I didn't think too much of it for a while. But after a few days I noticed that the static is there only when the car is moving. OK, so its wheel static. Static electricity from the wheels or brakes or something. OK that's not unusual either. But it is the combination that has me curious. This static only occurs when the car is moving and it only occurs at certain repeatable locations on my drive. Everyday when I turn the corner from X to Y, I get the static as the car is moving, but not when stopped at the same corner. And I never get the static when turning the corner from A to B. If it was power line, stopping the car wouldn't stop the static. If it is wheel static, why does it not happen all the time and happen only at certain locations. It seems as if these certain locations have something special about the pavement or the water content of the soil or something. None of that seems likely to me though, I see nothing changing in the pavement as I drive from an area of static to an area of non-static. It is not related to stepping on the brake or gas or shifting gears or going over bumps or any other aspect of the car that I can tell other than it's speed down the road. As an experiment, I attached a drag wire under the car. The wire drags on the ground to discharge any static build up the car. This made no difference. Another clue, we've had no rain here in a while. The static all stops during wet weather. Also I am in the Philadelphia area and the AM station is in the New York area so it is on the weak side. I've been a ham for over 30 years and I have a lot of experience with EMI, but this one has me scratching my head. The wheel static changes repeatably in different locations for no apparent reason. It's got to be something to do with the pavement. Anybody have any experience with this? Mark |
WHEEL STATIC ONLY ON SOME PATCHES OF PAVEMENT? WHY?
Mark wrote:
WHEEL STATIC ONLY ON SOME PATCHES OF PAVEMENT? WHY? With the financial mess, I have started to listen to AM radio in the car on the way to and from work for the past few weeks and I've noticed some random static at certain locations. At first I attributed this to some power line noise. Bit it didn't really sound like 60 Hz buzz hash, it was more random popcorn like but I know power lines can blow around in the wind and have strange discharges so I didn't think too much of it for a while. But after a few days I noticed that the static is there only when the car is moving. OK, so its wheel static. Static electricity from the wheels or brakes or something. OK that's not unusual either. But it is the combination that has me curious. This static only occurs when the car is moving and it only occurs at certain repeatable locations on my drive. Everyday when I turn the corner from X to Y, I get the static as the car is moving, but not when stopped at the same corner. And I never get the static when turning the corner from A to B. If it was power line, stopping the car wouldn't stop the static. If it is wheel static, why does it not happen all the time and happen only at certain locations. It seems as if these certain locations have something special about the pavement or the water content of the soil or something. None of that seems likely to me though, I see nothing changing in the pavement as I drive from an area of static to an area of non-static. It is not related to stepping on the brake or gas or shifting gears or going over bumps or any other aspect of the car that I can tell other than it's speed down the road. As an experiment, I attached a drag wire under the car. The wire drags on the ground to discharge any static build up the car. This made no difference. Another clue, we've had no rain here in a while. The static all stops during wet weather. Also I am in the Philadelphia area and the AM station is in the New York area so it is on the weak side. I've been a ham for over 30 years and I have a lot of experience with EMI, but this one has me scratching my head. The wheel static changes repeatably in different locations for no apparent reason. It's got to be something to do with the pavement. Anybody have any experience with this? Mark I used to run HF mobile, and had this same problem all the time. I had so many bonding straps under my truck that mechanics and oil change personnel would ask what they were for. I operated mainly on 40 and 80, and the engine/computer/fuel pump noise was very low. But, the tire noise was a big problem. For some reason, bias ply tires produced the most noise, and radials the least. There was always a difference being on the road, and the shoulder. On dirt roads, no problem at all. I tried graphite in the tires, but never thought to try it in the axle grease. bob baldwin WA5JOT bryan, texas |
WHEEL STATIC ONLY ON SOME PATCHES OF PAVEMENT? WHY?
On Nov 7, 8:34*am, Bob Baldwin wrote:
Mark wrote: WHEEL STATIC ONLY ON SOME PATCHES OF PAVEMENT? *WHY? With the financial mess, I have started to listen to AM radio in the car on the way to and from work for the past few weeks and I've noticed some random static at certain locations. *At first I attributed this to some power line noise. *Bit it didn't really sound like 60 Hz buzz hash, it was more random popcorn like but I know power lines can blow around in the wind and have strange discharges so I didn't think too much of it for a while. *But after a few days I noticed that the static is there only when the car is moving. * OK, so its wheel *static. Static electricity from the wheels or brakes or something. *OK that's not unusual either. * But it is the combination that has me curious. *This static only occurs when the car is moving and it only occurs at certain repeatable locations on my drive. Everyday when I turn the corner from X to Y, I get the static as the car is moving, but not when stopped at the same corner. * *And I never get the static when turning the corner from A to B. *If it was power line, stopping the car wouldn't stop the static. *If it is wheel static, why does it not happen all the time and happen only at certain locations. *It seems as if these certain locations have something special about the pavement or the water content of the soil or something. *None of that seems likely to me though, I see nothing changing in the pavement as I drive from an area of static to an area of non-static. * *It is not related to stepping on the brake or gas or shifting gears or going over bumps or any other aspect of the car that I can tell other than it's speed down the road. As an experiment, I attached a drag wire under the car. *The wire drags on the ground to discharge any static build up *the car. *This made no difference. * Another clue, we've had no rain here in a while. *The static all stops during wet weather. *Also I am in the Philadelphia area and the AM station is in the New York area so it is on the weak side. I've been a ham for over 30 years and I have a lot of experience with EMI, but this one has me scratching my head. *The *wheel static changes repeatably *in different locations for no apparent reason. It's got to be something to do with the pavement. *Anybody have any experience with this? Mark * I used to run HF mobile, and had this same problem all the time. I had so many bonding straps under my truck that mechanics and oil change personnel would ask what they were for. I operated mainly on 40 and 80, and the engine/computer/fuel pump noise was very low. But, the tire noise was a big problem. For some reason, bias ply tires produced the most noise, and radials the least. There was always a difference being on the road, and the shoulder. On dirt roads, no problem at all. I tried graphite in the tires, but never thought to try it in the axle grease. bob baldwin WA5JOT bryan, texas- Hide quoted text - - Show quoted text - A lot of time when you cross the state line the asphalt changes and you can hear the difference. I noticed a big difference as soon as I crossed into Ga from Fl the other day. Fl had the new asphalt that is suppose to give you more traction in the rain and Ga hadnt upgraded their's yet. I didnt realize the stactic was coming from the road/ tires until it turned off like someone threw a switch as soon as I crossed the line. Jimmie |
WHEEL STATIC ONLY ON SOME PATCHES OF PAVEMENT? WHY?
On Nov 7, 9:01*am, JIMMIE wrote:
On Nov 7, 8:34*am, Bob Baldwin wrote: Mark wrote: WHEEL STATIC ONLY ON SOME PATCHES OF PAVEMENT? *WHY? With the financial mess, I have started to listen to AM radio in the car on the way to and from work for the past few weeks and I've noticed some random static at certain locations. *At first I attributed this to some power line noise. *Bit it didn't really sound like 60 Hz buzz hash, it was more random popcorn like but I know power lines can blow around in the wind and have strange discharges so I didn't think too much of it for a while. *But after a few days I noticed that the static is there only when the car is moving. * OK, so its wheel *static. Static electricity from the wheels or brakes or something. *OK that's not unusual either. * But it is the combination that has me curious. *This static only occurs when the car is moving and it only occurs at certain repeatable locations on my drive. Everyday when I turn the corner from X to Y, I get the static as the car is moving, but not when stopped at the same corner. * *And I never get the static when turning the corner from A to B. *If it was power line, stopping the car wouldn't stop the static. *If it is wheel static, why does it not happen all the time and happen only at certain locations. *It seems as if these certain locations have something special about the pavement or the water content of the soil or something. *None of that seems likely to me though, I see nothing changing in the pavement as I drive from an area of static to an area of non-static. * *It is not related to stepping on the brake or gas or shifting gears or going over bumps or any other aspect of the car that I can tell other than it's speed down the road. As an experiment, I attached a drag wire under the car. *The wire drags on the ground to discharge any static build up *the car. *This made no difference. * Another clue, we've had no rain here in a while. *The static all stops during wet weather. *Also I am in the Philadelphia area and the AM station is in the New York area so it is on the weak side. I've been a ham for over 30 years and I have a lot of experience with EMI, but this one has me scratching my head. *The *wheel static changes repeatably *in different locations for no apparent reason. It's got to be something to do with the pavement. *Anybody have any experience with this? Mark * I used to run HF mobile, and had this same problem all the time. I had so many bonding straps under my truck that mechanics and oil change personnel would ask what they were for. I operated mainly on 40 and 80, and the engine/computer/fuel pump noise was very low. But, the tire noise was a big problem. For some reason, bias ply tires produced the most noise, and radials the least. There was always a difference being on the road, and the shoulder. On dirt roads, no problem at all. I tried graphite in the tires, but never thought to try it in the axle grease. bob baldwin WA5JOT bryan, texas- Hide quoted text - - Show quoted text - A lot of time when you cross the state line the asphalt changes and you can hear the difference. I noticed a big difference as soon as I crossed into Ga from Fl the other day. Fl had the new asphalt that is suppose to give you more traction in the rain and Ga hadnt upgraded their's yet. I didnt realize the stactic was coming from the road/ tires until it turned off like someone threw a switch as soon as I crossed the line. Jimmie If the road surface interface is not "keyed" to the moving part then statitic will always occur. If there is a contradiction in velocity of the two interfaced parts static will occur, if the two surfaces maintain the same velocity static will not occur. Thus static production depend purely on relative velocity which is governed by friction in your case. Art |
WHEEL STATIC ONLY ON SOME PATCHES OF PAVEMENT? WHY?
On Fri, 7 Nov 2008 13:17:06 -0800 (PST), Art Unwin
wrote: Some readers may be confused with the terminology of the original: If the road surface interface is not "keyed" to the moving part then Keyed: Scraping action alongside of a car for retribution. statitic will always occur. If there is a contradiction in velocity of the two interfaced parts static will occur, Contradiction: A failed interdiction. if the two surfaces maintain the same velocity static will not occur. Thus static production depend purely on relative velocity which is governed by friction in your case. Velocity: In southern Asia, larger than a town, smaller than a metropolis. Art Thus our original authur posits: if while driving around, the decaying hegemony of the counter-terrorists up and whisk you off to Ceylon for an interview - and you manage to scrape out of it (Keyed Contradiction), you will have escaped incarceration in the city of Velo (originally Veloceylon, that westerners have regrettably corrupted, as in the original here with Velocity) where static cling, the bane of haberdashers, is notable outside of the monsoon season. Haberdashers? Static cling? Yes, it is an exceptional reach in vocabulary to answer for noise from the pavement. Join us at rec.radio.amateur.antenna for further examples in this fascinating tour of creative expression. 73's Richard Clark, KB7QHC |
WHEEL STATIC ONLY ON SOME PATCHES OF PAVEMENT? WHY?
On Thu, 6 Nov 2008 02:24:48 -0500, Ed Cregger wrote:
"Tehrasha Darkon" wrote: On Wed, 5 Nov 2008, Mark wrote: I've been a ham for over 30 years and I have a lot of experience with EMI, but this one has me scratching my head. The wheel static changes repeatably in different locations for no apparent reason. It's got to be something to do with the pavement. Anybody have any experience with this? My guess is different lengths/types/orientation of rebar in the roadbed. Or electronic/magnetic sensors embedded in the road. I've been able to associate _hash_ , not *static* , to DOT-type roadside traffic informational signs -- usually the solar-assisted, battery operated style. My guess is they use some high-KHz power conversion and/or some not-so-well shielded electronics to operate the sign. The effect, though, is seen over a quarter mile, or less, section of the road. Jonesy -- Marvin L Jones | jonz | W3DHJ | linux 38.24N 104.55W | @ config.com | Jonesy | OS/2 * Killfiling google & XXXXbanter.com: jonz.net/ng.htm |
WHEEL STATIC ONLY ON SOME PATCHES OF PAVEMENT? WHY?
"Mark" wrote in message ... WHEEL STATIC ONLY ON SOME PATCHES OF PAVEMENT? WHY? With the financial mess, I have started to listen to AM radio in the car on the way to and from work for the past few weeks and I've noticed some random static at certain locations. At first I attributed this to some power line noise. Bit it didn't really sound like 60 Hz buzz hash, it was more random popcorn like but I know power lines can blow around in the wind and have strange discharges so I didn't think too much of it for a while. But after a few days I noticed that the static is there only when the car is moving. OK, so its wheel static. Static electricity from the wheels or brakes or something. OK that's not unusual either. But it is the combination that has me curious. This static only occurs when the car is moving and it only occurs at certain repeatable locations on my drive. Everyday when I turn the corner from X to Y, I get the static as the car is moving, but not when stopped at the same corner. And I never get the static when turning the corner from A to B. If it was power line, stopping the car wouldn't stop the static. If it is wheel static, why does it not happen all the time and happen only at certain locations. It seems as if these certain locations have something special about the pavement or the water content of the soil or something. None of that seems likely to me though, I see nothing changing in the pavement as I drive from an area of static to an area of non-static. It is not related to stepping on the brake or gas or shifting gears or going over bumps or any other aspect of the car that I can tell other than it's speed down the road. As an experiment, I attached a drag wire under the car. The wire drags on the ground to discharge any static build up the car. This made no difference. Another clue, we've had no rain here in a while. The static all stops during wet weather. Also I am in the Philadelphia area and the AM station is in the New York area so it is on the weak side. I've been a ham for over 30 years and I have a lot of experience with EMI, but this one has me scratching my head. The wheel static changes repeatably in different locations for no apparent reason. It's got to be something to do with the pavement. Anybody have any experience with this? Mark Mark, I came across this article, it may help you. http://www.k0bg.com/static.html 73 HarryH |
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