Noise issues (Mylaps): troubleshooting
This tutorial explains what to check in case you have problems with noise.
First, take a look at the decoder screen:
On the front of the decoder, you will find an information display designed to view and change the decoder settings. The status screen will show the following information:
– a: Decoder date/time, UTC when synchronized to GPS
– b: Timeline name
– c: blinks when connecting to Mylaps practice, steady when connected to Mylaps practice
– d: background noise indication
– e: Indication that hits are received, remains black when a transponder is being received by the loop
– f: Strength of last received transponder
– g: Number of received GpS satellites
– h: blinks when GpS receiver attached, steady when the decoder is locked to UTC time
– i: Message line
What if my background noise is higher than 40 points?
An increased background noise is an indication of a higher interference level picked up by the system. Every five seconds, a background noise measurement is performed by the decoder and sent to the computer. The noise level should be as low as possible, but as long as the received signal from the transponders is at least 60 points higher then the noise level detection will be reliable. If the noise level is higher than 70, then there is most likely something wrong with the installation.
Possible causes of high background noise levels:
– When the detection loop is damaged, a fluctuation in noise level will be noticeable, especially in wet conditions. If this is the case, please check the loop wire and coaxial for cuts or breakage.
– Electrical equipment too close (< 3m) to the loop or coaxial cable.
– Using a generator with a poor ground connection
– Use of DC/AC converter for AC power.
– Poor connections between the detection loop and the coaxial cable.
– BNC connector incorrectly fitted to the coaxial cable.
– poor ground connection of the AC power. If this is the case, ground the decoder by connecting the outside of the bNC connectors on the decoder to a piece of metal (copper rod or tube) that is in a fixed connection with the ground.
What if the received signal strength is below 100 points?
– If the signal strength is lower than 100 points, please check the position of the transponder. – If the signal strength is fluctuating heavily in combination with high noise levels, check the quality of the loop installation and coaxial cables.