Front logic display tutorial.

This tutorial is based on the use of a printed circuit board specially made , it is a matrix of 5x8 LED's .

Al that there is to do is solder on the 40 LED's and 8 resistors. The resistors are to adapt the intensity and the used tension. In my example i use 24 volts mostly available as this tension is used to drive the feet motors of R2D2.

Price for a set ( 2 PCB's) is 40 euro, the same as for a back logic PCB . Paypal at leon.b1@scarlet.be . The PCB is not longer available.

Here the PCB.

At the right/middle of the board the common + square . Left right and on top the place for the 8 resistors .

When using 24 volts the value of the resistors is 68.000ohm ( = 68Kohm) .

The placement of the different blue and white LED's is as follows.

The schematic. Just LED's connected in serie and one resistor added.

There are 8 strings of 5 LED's and on the board you find 8 command connection points, and one common connection point going to +24 volts.

This way the strings are placed, the same numbers of each row are in series, ( only serie one's wiring is showed here on the design.)

The commands can come from different steering devices , i use the cheap PIC flasher K169. If you look for this PIC flasher do a " google" on K169 pic flasher and you will find several places where these are sold.

Solder row by row to have easy acces.

Cut of the excess of wire from the LED's before soldering the next row.

With the component side facing upwards and the common + connecting point at the right , as on the photo below, put the longest legs of the LED's at the left, when putting the LED in place.!

All LED's soldered in

This way the resistors are placed. All 8 are 68Kohm. Leaving the 8 square holes where the commands are soldered.

In the surround. As you can see 5x8 is just what we need to fill the surround completely, i suppose the 5x9 is only good for fibers, wich are less than 3mm I think..

Working example .................

Mounted in R2D2 ..........

I did not use a bezel, as i like the LED's sitting IN the surround and not just behind the surround. As the LED's are sitting really one next to the other on the PCB i suppose you can fit them in any bezel if you use somewhat longer legs , wich can be bended to fit the bezel. ( this was succesfully done by builders on the rear logic PCB ) .