Slot Car Controllers, Spares and Accessories


LDR Track Sensor #1

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  • Regular price £5.00

LDR (Light Dependant Resistor)  for the Track Lap Counter Sensor.
Related product: Track Sensor Interface 

This LDR sensor is a simple and very effective device for detecting the passage of a slot car over the start/finish line. 

  • Used in conjunction with the Track Lap Counter Sensor
  • No need to have exact alignment of transmitters overhead in the gantry to sensors in the track
  • Ambient room light or general light from the track gantry over the start line. 
  • Fits next to either of the track power rails.
  • Mounted neatly from underneath to lie flush with the track surface. 
  • LDR units are mounted with a 5.5mm hole drilled through the track next to one of the power rails
  • Easy to just wipe clean
  • Decide on the start line position and mark out the LDR mouting positions next to one of the power rails on each lane.
  • Cut lengths of thin dual core wires, such as alarm wiring cable, to run from the Track Lap Counter Sensor unit up to the start line. This cable will solder to the two LDR legs. ( It does not matter which way around they are connected )
  • Solder the wires to the LDR legs and use some sort of insulating sheath to prevent the legs from touching together. 
  • Where you marked the track, drill a 5.5mm hole into the track  for each LDR to mount into. 
  • Push the LDR head from underneath the track through the hole to meet flush with the track surface, or till the tab prevents it from going any deeper. 
  • Connect the other end of the cable to the Track Lap Counter Sensor terminals. One pair of terminals per lane. 
  • Apply the power supply to the Lap Sensor unit and select the appropriate pluse configuration for your software and interface. (Positive or Negative going pulses)
  • Selection of Positive or Negative going pulses does not need any wiring changes. Simply wire as per the diagram and you can change the mode switch any time. 
  • Click here for Wiring Diagram