(warning: lots of hi-res pictures, long download)
This page is for people who have some kind of mechanical device such
as a spinner already built and want to add the electronics to connect it to the
Opti-Pac Plus. Only the electrical connections are covered here, you'll still
have to work out a method of mounting the sensors or PCB to your mechanical
device and you will need a spoked disk mounted on the shaft. Two methods are
covered: Using a Happ Controls Optical PCB and Using a pair of Opto Switches.
Happ Optical PCB.
This is what the PCB
looks like and shows the connections. Simply wire up each pin as shown on the
picture to the corresponding connection on the Opti-Pac.
Opto Switches.
This method uses a pair
of standard opto-switches. These can be obtained from electronics supply
stores. The cheapest type will do, which simply have a LED in one side and a
photo-transistor on the other. They usually cost less than $1.
In the UK
these can be obtained from Bardwells.
their product description is "2 x Slotted opto switches 3mm slot" in the
"optos" section. (Price 60p for the pair) In the US try Digi-Key. An example
part number is QVB11334 which you can enter in the search box
here.
You will also need a 220R resistor.
The switches will be marked "E" and "S"
on each side. the "E" side=Emitter and "S"="Sensor" (may also be "D"=Detector).
First glue the sensors together with the "E" marks alongside each other as
shown below: Then turn over the assembly. IMPORTANT: The pictures below show
the assembly with the "E" sides at the TOP.
Solder a 220R resistor as shown between the two
diagonally opposite pins on the right-hand sensor. Solder the lower left pin of
the right-hand sensor to the lower left-hand pin on the left-hand sensor (bend
the pin around).
Solder the top left pin of the right sensor to the top
right pin of the left sensor. (Hopefully the picture is easier to understand
than this description!). Cut off any protruding pins of these two you just
linked.
You should end up with four protruding pins left.
Connect these to the Opti-Pac Plus. The picture shows push-on connectors but
you could just solder wires to each of the four pins. Some shrink-fit sleeving
finishes off the job. For this configuration the jumpers are set to "A/LO" on
the Opti-Pac.
Now mount the assembly on your mechanics by whatever method
works. The optical wheel should be positioned centrally in the notch of the
sensors.
If you want to have a go at making your own PCB for
this, Tony Jimenez has very kindly supplied a design which he has produced.
Click here to download
the file which contains the PCB plot in BMP format and a readme file. Thanks
Tony!
