Zaccaria led display's 8 digits.

Board type 1B1168 ( 4x2 glass dislay's)

There are at least two different 8 digits boards,, the one here1B1168 has 4x2 separate glasdisplay's.

Soon after i designed the led display for Bally i found out that it could be done for Zaccaria the same way.The schematic is almost identical .All we have to do to transform the Zaccaria display board to make it ready to steer the led display's , is to change 8 resistors, cut some away and add some jumpers.

This is the 8 digits 4x2 Zaccaria display.

We need a printed circuit to fix the 8 led display's. This print comes at the place of the glas dispaly.


The design of the print.


The freshly made print. The print is slightly to large for a 2x4 display ( the print was designed for a 8 full glass display type) . We have to cut the print just at the first and the last digit, then it fits..( See photo ) By cutting we loose the connections point for the segments, who are situated just besides digit one.... No harm done we solder the segment connections directly on the runs. ( see photo,of the completed display further in the article ) .

The print cutted just at the last and first display.

Something to fix the print

The print is 14 x 5 cm. We use the excisting holes to fix the new print.

Second possiblility , work on a universal print.

We use a piece of universal print, with two hole for every solder-island. The dimensions are 14x5cm. You can see a realisation of such a print on the pages for Bally 7 digits display, where i made such a board. The way how to make it is exactly the same for this 8 digts board, of course for the connections follow these pages..


A piece of universal board ready to be made at te exact dimensions.

We mount the 7 displays and connect all 7 a, b, c, ..pins together, on the common anodes a short wire. Now it will be 8 display's.

The 7 display mount.

Back side the orange wires are the common anodes. The a,b,c. lines are all connected together.

Mounted with the led display's here type MAN8610. For the 8 digit Zaccaria use SA56-11HWA types.

The backside, the red wires are the digit select, the white wire the connection to the a,b,c,d,e,f,g lines. For the 8 digits Zaccaria see connections further down this article.


A working example (7 digits) .

The adaptions of the display board.

What do we change on the original board to make it ready to drive led displays? Here are the changes. Use also the complete schematic to have an overview of the whole. You find it here ........


Here we see the part where the digit selection is made ( digit 1 ) De changes to apply ( 6 times) are the replacement of a resistor by a jumper, here for digit 1 = R17 . The 140 volt line will be altered so it will have only 5 volts. The diodes wil be cut off ( Here for digit one D1)


The figure on the led display is made up of 7 strait lines , here we see the steering of these lines, starting at the left .( a,b,c,...) We change resistors R9 to R15 by 100 ohm resistors, eliminate resistors R2 to R8, and replace resistors R32 to R38 by a jumper.That's all there is to modifie.


Practical realisation.

Remove the row resistors R2,3,4,5,6,7,8. Replace R9,10,11,12,13,14,15 by resistors of 100 ohm's, ( both series resistors indicated with the blue arrow ) , and R32,33,34,35,36,37,38 by jumpers. ( white arrow)


Next remove the row resistors R17,19,21,23,25,27,29 and 31 and replace them with jumpers.( white arrow)

The last thing to do is to cut of the arrival of the 140 volts.The 140 volts arrives at pin 19 of the input connector CN1, you see the run going to condenser C4. Cut this run near the connection of C4 and now connect C4 to the neartby +side of C5, a small jumper does the trick.This conclude the alterations. ( On the photo indicated with the white arrow the place where the run is cut , and the jumper between +5 volts and C4.)


Connecting the display.

When using a print desing like the one in this article, use a 16mm display type SA56-11HWA.

The connections of a SA56-11HWA type display.


The digits are connected at the holes left by the removed diodes D1 to D8 use the holes at the banded side. Where D1 is for the ubits and D8 for the ten millions. The segments are connected to the newly placed resistors of 100 ohm, R9 to R15.

R9 goes to a, R10 to b, R11 to c, R12 to d, R13 to e, R14 to f and R15 to g. Connect at the side of the resistor that points to the outher edge of the pcb board.

The white wires going to the digits. The green wires are soldered directly at the runs between the segments , this because we had to cut away the original soldering point to adapt the overall sise of the printed circuit. As you see there is no difficulty to solder the wires on the runs, as the runs are large enought.

The completed led display connected to the pinball

Adapting the 5 volts regulator

When installing 5 or 6 extra Led display's the 5 volts regulator will be extra charged. The 78H05KC can deliver 5 amps. The Zaccaria pinball uses only 1,5 amps. So there is sufficient reserve to drive the 5/6 LED display's.