To connect sensors or other circuits to the ports on the Handyboard, you will have to
make a suitable 3-pin plug, and solder flexible wires to it.
You should use heat-shrink tube to cover these joints, both for
insulation and for mechanical strength.
The three connections to the Handyboard input ports are as
shown in the diagram on the right. The picture shows a
3-pin plug connected to port 2 on a Handyboard.
Take care to connect all the wires to your circuit correctly.
If your circuit produces more than one signal, you need only make the +5V
and 0V connections once.
Making a plug
Cut a 4-pin plug from the strip of pins in bag
Z.
Use a pliers to pull out one of the inner
pins, to leave a 3-pin plug as required.
Use the pliers to grip the plastic part of the
plug, and press the pins down on some scrap paper. Be
careful here - the pins will slide suddenly through the
plastic!
The aim
is to get a more symmetrical arrangement, like this:
There should be enough pin length on one side to solder
wires to it, and enough on the other side to connect to the
Handyboard socket.
Soldering the wires
If you have not been shown how to solder, STOP.
Read the soldering page and then ask
for instruction.
The technique here is a little different from soldering on
strip-board:
Remove the insulation using a wire stripper.
Twist the strands of wire together
lightly.
Tin the end of the wire - heat it from below
and melt a little solder onto it.
At this point, push some heat-shrink tube onto the
wire. Slide it away from where you will be soldering.
Tin the pins to which you will solder the wires - not too much
heat, or the plastic part of the plug will melt!
Hold each wire beside the appropriate pin, so that it touches it along most of
its length. Touch both the wire and the pin with the (clean) tip of the
soldering iron. The solder on the wire and the pin should melt and flow together. Let
the joint cool.
Insulating the joints
Slide the heat-shrink tube along the wires to
cover the joints.
Heat gently, from both sides, using the
hot-air gun.
The finished plug should look like this.
Plaiting or braiding the wires is optional - it makes the
whole assembly stronger as well as neater.
