How to Extend the Range of New HW763 Touch Sensors

The original version of this sensor had quite a long range out to 10mm. The new version has been adjusted to have a much shorter range out to 2mm. I mount these sensors behind my project panels and need at least 5-6mm pickup distance.

To extend the pickup range of the new version you must disconnect the PCB touch plate and install your own pickup loop. The touch plate on the reverse side of the PCB can be disconnected from the TP223 chip by drilling the plated through hole in the bottom right hand corner of the PCB. You can then solder your own pickup loop directly to pin 3 or to the small pad above the drilled hole.

Short length of multi stranded hookup wire, solder and soldering iron. 3.5mm drill bit.

The original board with 10mm range is identified by two large pads in the bottom right hand corner.

Here's a new board I modified for 15mm pickup range attaching the pickup loop to the small pad above the plated through hole I drilled. The wire is simply a single strand of wire plucked from some multi stranded hook up wire.

It doesn't matter if the loop is closed short circuit or not. I prefer to twist the loop closed so that the loop remains nicely formed.

A little off centre, the darkish spot in this blurred image is the plated hole that no longer connects the touch plate to the IC. You know the touch plate is disconnected when this hole stands alone with only PCB material around the hole. To drill the connecting hole I used 5-10 turns of a 3.5mm drill bit in a mini hand drill.

Secure the pickup loop to the PCB. I use hot melt glue but any non conducting solid glue would work.