Zaccaria led display's. Type 7 digits.
Intended for second generation = Farfalla and others.
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 7 resistors, cut some away and add some jumpers.
Zaccaria has a few different types of display's , these for the later games have 7 or 8 digits. This pages are intended for the 7 digit games , the 8 digits display will follow soon.
This is the 7 digits Zaccaria display.
Starting the project
We can use the same design of PCB that is used for the Bally 7 digits display, important is to use for Zaccaria 18mm ( large) leddisplays to respect the overall lenght of the displayboard. Here the design for the PCB. Pictures shows it all...
The final print design the same as the one for Bally.
A simple piece to fix the print
The print is 14 by 5 cm. We use the original holes to fix the print.
On a board of this dimensions you make the printed circuit. Hopefully it will be available "ready made" soon!
The home made 7 digits printed circuit.
Second solution, work directly on an universal printed circuit board.
We use an universal print board with two holes in every solder-island. The dimensions are again 14x5cm.
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.
7 Display's mounted.
Back side, the red wires are the 7 anodes. The a,b,c.. lines are "jumped" together.
Mounted with the led display's type MAN8610.
The backside, the red wires are the digit select, the white wire the connection to the a,b,c,d,e,f,g lines.
The connections are simple, all connections goes to the old solder points where the glass display was.That is for the a line pin 1, b line pin 3, c line pin 5, d line pin 33, e line pin 35, f line pin 39, and g line pin 37. The digit select for units to pin 2, ten's to pin 8, hunderds to pin 14, thousands to pin 24, thenthousands to pin 28, hunderdthousands to pin 32 and millions to pin 38.
Connected at the pinball
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 = R43 ,and the 140 volt line will be altered so it will have only 5 volts.
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 R8 to R14 by 100 ohm resistors, eliminate resistors R1 to R7, and replace resistors R15 to R21 bij a jumper.That's all there is to modifie.
Remove the row resistors R1,2,3,4,5,6,7. Replace R8,9,10,11,12,13,14 by resistors of 100 ohm's, ( both series resistors indicated with the yellow arrow ) , and R15,16,17,18,19,20,21 bij jumpers. ( white arrow)
Next remove the row resistors R43,45,47,49,51,53 and 55 replace them with jumpers.( blue 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.
You can use all types of display's certainly when you use an universal print board. When we use a "ready made" print the common anode has to be at the pin foreseen on the printed circuit . All other lines are connected with the corresponding line coming from the original display board. The display has to be max 18mm. large otherwise the whole row displays becomes to large to fit.
The connections of a MAN8610 type display.
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.