We are,currently, training 2 new speaker builders..  until we get them up to speed, we will have 10 day production que.  We apologize for the delays.. we build one at a time.. no assembly lines !


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Home OPT-3
Item Code: OPT-3
OPT-3 Item Code: OPT-3


  • Roll your own LED optoisolator module.

Includes Hi-bright white LED, photoresistor cell, and heatshrink tubing. You glue the two devices together head-to-head and then slip the heatshrink over them. You fill the ends of the heat shrink tubing with opaque glue, allow it to harden, and you're ready to go. The LDR (light dependent resistor) cell has an ON resistance of <1000 ohms and an OFF resistance of >20 Meg ohms.

Click here for build instructions