View Full Version : Interference Over Core Loop

2008.01.10, 10:14 PM
Hi Guys,

I've seen a couple of other threads about interference but none of the potential solutions seemed to help me.

I have my Core loop set up as indicated in the instructions and routed out a channel in my RCP track to embed it in.

My track is on the 2nd floor of a converted factory to loft space type building with a concrete floor. I have a layer of 4 mil Mylar under the core section of the track.

I get interference ranging from barely noticeably to complete looping of the car as it crosses over the loop. Also, when I initially scan a car it jumps all over the track and even drives a short distance by itself.

Cars tried:

Ford GT (2 - 1 completely stock and one with 3Racing motor mount and suspension damper)
Ferrari Enzo
Nissan 350Z
Toyota Overland

I tried a longer car antenna.

I tried isolating the antenna from any carbon in the damper plate as well as move the antenna completely off the damper. Carbon had cause problems on my RC planes but isolating it should stop any related issues although I do think that the interference is more noticeable on cars with mods to the suspension as opposed to bone stock.

I tried reorienting the transponder in the car and did get a bit of reduction on the Enzo but not on the Ford GT.

I tried turning off my Wi-Fi on the computer.

I tried turning off the Mercury Vapor lights to no avail.

It doesn't seem to affect my Overland as much. ??Proximity of the transponder to the car electronics??

Anyone tried 2.4GHz receivers yet?

So, I am just looking for some suggestions to try so I can enjoy my lap timer more!



2008.01.10, 10:19 PM
Greg, what I have had sucess with is the following. sometimes when running on Concrete you can get some interference from the rebar in the concrete.

Have you tried shifting the location of the track by 12" or so? I'd sugest that. you can also position the starting line in a different location for testing. this will help trouble shoot the problem.

Some frequencies are more prone to glitch than other. I beleive it was channel 3 that was the worst. give that a try?

2008.01.10, 10:59 PM
haven't got a core yet... but going through this is nice to know :D

2008.01.13, 11:51 AM

I tried moving the track a bit 6" here or 12" there and there seems to be some difference likely due to, as Brian said, the rebar location in the concrete. Would a stud finder or some similar device help find where the bars are? I'd bet that if the rebar affects me it affects other folks on concrete too. If there is a location within the rebar grid that is better that another we should map it for future reference.

A more noticeable change for the better was to switch from Channel 4 to 6. I have next to no interference on 6 and 4 is consistently getting affected. 2 also is better although I have not run much on that one yet.

Would a lead sheet, or some other material, under the loop block effect of the rebar grid?

More later,


2008.01.13, 06:31 PM
I put wood under mine. I run on a concrete driveway. It helps, but it also creates quite a bump.

You can't use anything metal because the loop is creating a magnetic field.

Rubber is best. Try sandwiching the loop between RCP layers. Trouble is, this creates an even bigger bump.

We get the same thing as you with the Freq's.

At our club we have every am freq you can buy. (atomic makes a ton that are not really leagal in the US). Some channels have no issues and others you just can't use. For example, the car turns into the wall as you pass the loop with xmods 10.

If you can find them, look for an xmod racing crystal set. You get 6 freq's for around $15 on ebay.

We only race 4 at a time so it's just a matter of finding 4 that will work that day and then swapping out for the race.

2008.01.13, 10:45 PM
did anybody run theirs on a basketball court with hardwood floors? how about badminton courst? over here there are badminton courts with a rubberlike material surface, i think they call it taraflex... i think some volleyball courts use the same material... or probably a surface that's not concrete (with rebars)... i.e. carpets and such...

wondering if results would generally be better on non concrete surfaces...