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Only glitching when racing...

Only glitching when racing...

Old 06-13-2004, 04:47 PM
  #16  
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My dad used the XR2 AM Highband and had the same problem....Nobody was on his channel AM or FM & it only occoured during races....

Could have to do with transponder/placeage
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Old 06-13-2004, 08:07 PM
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Originally posted by kufman
Any type of transponder at all?
I have one of the club transponders mounted in the windshield of the body. It's not above any electronics.
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Old 06-13-2004, 08:38 PM
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Originally posted by fatdoggy
I have one of the club transponders mounted in the windshield of the body. It's not above any electronics.
My dad did the same...It could be an issue with handout transponers
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Old 06-13-2004, 09:39 PM
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Originally posted by The Black Kat
My dad did the same...It could be an issue with handout transponers
Doubtful.

Am radios are more prone to RF noise problems then Fm.How old is the radio and crystals? Your also running a double decked car.These are sometimes prone to glitching due to different factors.I know of a guy who after a major crash started to glitch bad.after he replaced the chassis it was all better.Could be metal parts that are mounted to the carbon fibre chassis causing the problems from them rubbing.All the other suggestions are good but doubt its the transponder.
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Old 06-13-2004, 11:13 PM
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racenut123 - The radio is about 1 1/2 years old. I'm running the C4, pretty much the whole car except the suspension is either metal or graphite.

The Black Kat - I doubt it the transponder, I've never had any problems with them before.

Thanks for the help guys, I'll just do what people have said to do above and hope it doesn't happen again on saturday.
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Old 06-13-2004, 11:15 PM
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Originally posted by fatdoggy
The Black Kat - I doubt it the transponder, I've never had any problems with them before.
Never say never.
I personally had encounter this problem.
Usually due to a bad transponder.
But then, maybe its just me.
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Old 06-14-2004, 07:21 AM
  #22  
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the transponder must mount far away from receiver.

did u glitch after the race?

try reverse the tx and rx crystal

if twisting the wire make better try resolder all wiring and change new connectors
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Old 06-14-2004, 07:50 AM
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Originally posted by racenut123
Doubtful.

Am radios are more prone to RF noise problems then Fm.How old is the radio and crystals? Your also running a double decked car.These are sometimes prone to glitching due to different factors.I know of a guy who after a major crash started to glitch bad.after he replaced the chassis it was all better.Could be metal parts that are mounted to the carbon fibre chassis causing the problems from them rubbing.All the other suggestions are good but doubt its the transponder.
We made sure that the antenna was not rubbing against anything...It was in an MR-4TC (I doubt that helps at all)

Knowing my dad...it was a brand new radio (no wonder I can't get new springs)
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Old 06-14-2004, 02:35 PM
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Default Transponder?

I have had problems with transponders mounted close to my Rx. Had to move it and the glitching went away. I have also had problems with the car glitching under the thing that receives the signal for the transponder. It wasn't causing the problem, but it glitched as I passed under it every lap. I had wiring problems, the bridge just set it off.
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Old 06-14-2004, 05:52 PM
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I once owned a JR XR3 and had nothing but glitch problems with it in similar situations to what you are describing. After doing some research to confirm a theory that I had, I discovered something interesting.

First off, I theorized that the JR receiver is poorly designed. Basically, the spec that I believed was at issue is called "alternate channel selectivity." This is a measure of the receiver's ability to accept a narrow frequency range and reject all others. To test this, I raced with buddies that were running adjacent frequencies to what I was running on. We stood several feet away from each other on the drivers stand and raced. When my car was in the clear, it was fine, but when it got close to other cars, it would almost always glitch. Now granted, in my test, I could not avoid an adjacent channel by design, but this could be part of the problem. Then, as I was researching specs on their radios, I discovered that the transmitter output power is quite a bit lower than on many other brands of radio. So, my theory is that the combination of poor alternate channel selectivity and reduced transmitter power = glitches while racing. The way I fixed the problem was to put the XR3 on Ebay and buy a KO Mars. I have a buddy that didn't want to go that route and decided to experiment with receivers instead. He uses Novak XXL receivers and rarely has glitching problems, so you might give that a shot.

Since I had that experience with JR, I will not buy another JR radio. Some people have good luck with them, but most that I know have not. I'm sure that's probably not what you were hoping to hear, but that has been my experience. I hope that helps you get the problems sorted out.
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Old 06-14-2004, 05:56 PM
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I just thought of another strange situation where I had repeatable glitching problems. This was with a Futaba radio (which is likely not relevant.) It turned out that one battery pack had a cold solder joint on one battery bar. It charged fine and ran fine, but caused the car to glitch a lot for some reason and mainly with the throttle full open. Once I narrowed the problem down to that pack, I resoldered everything and it was fine.
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Old 06-14-2004, 09:25 PM
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rcsabah - No the transponder isn't even close to the rx and I don't use connectors.

psycho - If I keep having problems I've got a 27mhz perfex Tx and Rx I'll use till I can get a quality FM radio.

Thanks for the help everybody. If it keeps up I'll just stop using it and start saving for a decient radio.
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Old 06-14-2004, 10:03 PM
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Wow! Fatdoggy and I have the same issue. And we both have JR 75 hz radios/receivers.

Virtually all my glitching occurs more than 40 feet away from me.

I am using rechargables in my radio; so, my next test will be to try 1.5 V AA batteries.

Great posts all!
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Old 06-14-2004, 10:10 PM
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Bill, I was marshalling your race on Sat and I only saw you glitch when you were in traffic. Does that seem right? Victor should be able to tighten you up with a KO Helios.
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Old 06-14-2004, 11:14 PM
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Originally posted by psycho
Bill, I was marshalling your race on Sat and I only saw you glitch when you were in traffic. Does that seem right? Victor should be able to tighten you up with a KO Helios.
Hi Psycho,

Remember I had that BIG lead with no one else around when it initially started. Consisted of errant steering inputs (as if I'm not bad enough) and slow downs to only half speed.

OK, two votes now for the KO. You and John Hicks.
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