Hey all,

I bought a new MyLaps RC4 transponder from A Main a few weeks back. I installed it in a TC car, but it wasn't being picked up by one of our tracks (we have 2) in the position I mounted it in. I moved it and it got picked up intermittently. However, it wasn't being picked up at all by the decoder on our other track at all. I even tried it in my other TC car which has an RC4 transponder that works fine, and it that car it was also not picked up. So I sent it back to A Main for an exchange.

Well, I got a 2nd, brand new RC4 transponder and that one is also not being picked up by our track either. People suggested that I may have plugged it in backwards, or that my BEC (Hobbywing Justock) is damaged. Well, I triple-checked, it was plugged in correctly, and I just measured the voltage at the pins, and it has the same output as my other Justock with the working RC4 transponder.

It's hard to believe that I got two bad transponders in a row. Is there any way I can diagnose what's going on? I'm mounting it using sticky servo tape on top of a bumper brace at the front of the car. I tried to even hang it from the side of the car, still no go.

Any ideas would be appreciated.

Is there anyone else at all having trouble counting? People with older AMB personals?
I ask because when we got the new RC4 decoder at our track, we had a defective one. Some people had no trouble counting, others had all kinds of trouble. Race director was pulling his hair out trying to figure it out. He ordered new loop, new counting software, etc. We finaly borrowed another decoder from another track and it worked flawlessly. Had mylaps exchange the bad decoder, and no problems since.
It would be crazy to have two tracks with bad decoders, but I guess no more crazy than having two bad transponders in a row.

Although a lot of guys are running the older AMB transponders, many are running the RC4, including me (I have two good ones). So, I don't think it's our decoder. I may try some more tests by swapping my good RC4s into the "bad" car and verifying they work. A part of me is paranoid that something about that car is damaging them, though. But they blink as if all is well. This is a hard one to diagnose for sure.

is it on a Y cable? If so remove cable.
Turn your wheels to the max. Does the LED dim?

Nope, directly plugged in. I measured the voltage at the pins at idle, with full throttle, and with full throttle while turning the wheels full lock back and forth... it didn't drop at all. Plus, when I was trying to test the transponder, I literally moved the car back and forth across the decoder by hand, no throttle or steering applied.

I think I'm going to bite the bullet and try one of my good RC4s in that car to see if they get picked up. If so, and this "bad" one doesn't get picked up in the good car, then I have another lemon. I can't believe my luck, I should play the lottery

Have someone watch the decoder as you pass the loop. The MyLaps RC3/4 decoders have a display screen and it will give a reading of the signal strength of the transponder. Preferably 100+ but no lower than 60. That number is just to the left of the diagonal bar that turns black as the transponder passes the loop.

Is that a general bar/view, or one that shows up once a transponder is picked up? I ask since I wasn't being picked up at all, so no driver time window was showing up.

Our local track owner told me that some of the newer transponders are not working, even with the latest software update for the lap counter software. He said the hybrid transponders work fine. Have you contacted Mylaps customer support about the issue?

We've had some brand new RC4 transponders just not work with our decoders as well. This was after the upgrade, hybrids seem to be fine.

this is why I got the hybrid one. figured they didn't run out and buy the newest system and I didn't want to risk saving a few $ and have one that wouldn't work.

I'll contact MyLaps directly tomorrow, if I can, I feel bad about sending this second one back to AMain again. It kinds sucks, though, as the last two RC4s I bought have been flawless. I guess I'll try to exchange this one for a hybrid as well, then.