Wednesday, 25 November 2020

Pi2jamma v2 Premium Version Release

Find here our famous Pi2Jamma v 2 premium vesrion. This is one of our best products and of course always on stock. 


The Premium offers the following additional features compared to the Pro version:

  •     Adjustable screen color strength via the built-in RGB amplifier    An adjustment axle for the strength of the screen colors
  •     Chamma support: Button 6 for players 1 and 2 are placed on Jamma pin 27 and pin e. This jamma extension is often used in 6 Buttons Arcade Cab. The Chamma support can be switched on and off.
  •     CPS2 kickharness interface. Many Candy Cabs support this interface for Button 4, 5, 6 Player 1 and Player 2
  •     Extra pin header interface for video signals: External image converters or similar can be connected here.
  •     Extra pin header interface for all free GPIO pins of the Raspberry Pi
  •     Support of the switch signal, can be switched on and off

Both Pi2Jamma v2 versions offer

  • native 15 khz RGBS CRT video output for standard arcade RGB CRT,
  • direct lagless controls
  • sound amplifier with volume control
  • 6 Button Support for each player
  • Jamma interface. 
  • new design for mounting raspberry pi and an enclosure 
  • Support all Rasperry Pi Versions with 40 pin gpio : rpi3b, rpi3b+, rpi4


Pi2jamma v2 pro version

Find here the pi2jamma v2 pro version. The pro version has all features to set up a simple standard gaming system for a Jamma interface Arcade cabinet.

  • Supports 15 kHz RGBS standard Arcade RGB CRTs 
  • Jamma Interface with 6 buttons per player extension 
  • Audio Amplifier 
  • Volume knop for Audio Amplifier 
  • 40 pin gpio interface 
  • Video RGB amplifier 
  • Audio jack 
  • Screw holes for Raspberry Pi and enclosure

Friday, 20 November 2020


Find here the new CRT RGB PICTURE SHIFTER. 

It's available now at and other distribution partners.

The CRT RGB picture shifter pcb is a little device that shifts a CRT RGB picture  from left to right and vice versa.

It will be connected between Picture RGBS source and the CRT.


  • It has a input RGB Scart and a output RGB Scart connector.
  • Position of picture will be adjusted with a Axle. 
  • Sync resistance of 75 Ohm can be switched on and off with a jumper. 
  • Led shows if unit is powered on or off. 
  • Standard power plug of 2,1mm / 5,5mm inner pole plus usable on all arcadeforge devices. 
  • Power supply needs 5V with 0,5A, inner pole plus, 2,1mm / 5,5mm 
  • Unit has a power on and off switch 

Saturday, 29 August 2020

Roadshow pinball coin door bracket

This is the bracket in the coin door for closing the 2 switches. 

Roadshow repair eyes not moving left

Time go deeper in the docs till eyes still not moving. 

I checked ops manual for the connector and coils eyes moving left and right. After that I refer to Williams schematic. 

Roadshow Flipper Repair and Restoration

Here's is the first part of repairing Ted froa roadshow pinball. Removing Ted needs the dissambly of various parts. It's one of the most challenging repairs someone can face in pinball restoration. 

Issue is that eyes not moving left. 

Turns out coil SM-30-1100 is defect. So I replaced it and expected it to work again. But the issue still exists. Back to the documents then. 

Currently repairing a roadshow that has an issue with eyes left movement. 

I'm wondering if Pin2 output is correct. It should be 50v something. 

Currently repairing a roadshow that has an issue with eyes left movement. 

I'm wondering if Pin2 output is correct. It should be 50v something. 

Thursday, 2 July 2020

How to connect a pi2jamma to a Jamma connector

Just take a look at the pictures.

Pin 1 is on the right hand side. Parts side up. 

Tuesday, 30 June 2020

Battle Zone Atari Vector repaired

What should I say. The ls194 on d6 and TL082cp replacement brought it back 

Sunday, 21 June 2020

Fluke 9010a

Fluke 9010a is fun!

Battlezone repair fluke 9010a

Find here some information testing a battlezone arcade pcb with a fluke 9010a. Turn active force line off in setup. 

Rom tests 9010a/Scripts/Atari/Battlezone/BATTLEZONE2.txt
DPY-TESTING V-ROM 03642201 A3 

   ROM TEST @ 3000-37FF SIG 6628

   DPY-TESTING V ROM 03642101 B C3

   ROM TEST @ 3800-3FFF SIG F6EA

   DPY-TESTING PGM ROM 036414a01 E1

   ROM TEST @ 5000-57FF SIG B9B1

   DPY-TESTING PGM ROM 03641301 H1

   ROM TEST @ 5800-5FFF SIG 62A4

   DPY-TESTING PGM ROM 03641201 J1

   ROM TEST @ 6000-67FF SIG E68A

   DPY-TESTING PGM ROM 03641101 K1

   ROM TEST @ 6800-6FFF SIG ECB0

   DPY-TESTING PGM ROM 03641001 L M1

   ROM TEST @ 7000-77FF SIG 5D24


   ROM TEST @ 7800-7FFF SIG 4CCE

RAM tests 9010a/Scripts/Atari/Battlezone/BATTLEZONE3.txt

H2, j2 is the program memory. 


   RAM SHORT @ 0000-03FF



   RAM SHORT @ 2000-23FF




   RAM SHORT @ 2400-27FF



   RAM SHORT @ 2800-2BFF




   RAM SHORT @ 2C00-2FFF

Test of the vector output.
If RAM and Rom is ok, probe pins 2 through 11 of the 6012 DACs that are at the edge of the video section, while the board is in test mode. These pins are the inputs to the DACs. You should see toggling on all lines, for both DACs. 
If you do, then the vector generator is working, and one or more of the analog chips after the DACs are bad (and/or the DACs themselves, which is common), 
If the DAC inputs aren't toggling, you have issues with the vector generator section. 
Viewing output x and y on the scope. Turn on the xy mode. Connect probes to xout and yout. 

Memory Map
Tutorial for ram in circuit test
RAM 2114 TESTER arduinoür-2114-rams-auf-basis-eines-arduino-nano/&postID=1429419
For reading roms use chip type 2176 generic type. 
Tests are shown here

Monday, 9 March 2020

Pinball Shadow : Testing the DMD

    Diagnosing Other Problems.
    If you are sure the display itself is working, there are some other things to check when a DMD doesn't work.

    Make sure to check fuses F601 and F602 (all WPC games). F601 is used for +62 volts, and F602 is used for -113, -125 volts. On WPC-S and before, these are 3/8 amp fast-blo 1.25" fuses. On WPC-95, these are T0.315 amp 5x20mm fuses.
It's easier to test voltages at the dot matrix display itself than at the
controller board. Use the "key" pin for reference to figure out which is pin 1
and pin 8.

testing voltages

    Testing DMD Voltages.
    If the fuses are good on the dot matrix controller board (or audio/visual board for WPC-95), you should next check the power at the DMD itself. Voltages used are +62, +12, +5, -113 and -125. Check these voltages at the dot matrix display, or at connector J604 on the controller board. The pin out is:
    • Pin 1: -125 volts
    • Pin 2: -113 volts
    • Pin 3: Key
    • Pin 4: Ground
    • Pin 5: Ground
    • Pin 6: +5 volts
    • Pin 7: +12 volts
    • Pin 8: +62 volts
    If the -125 volts is missing, -113 volts will be missing too. All voltages should be pretty much right at the above specs. If they are not, you need to rebuild the dot matrix controller. 
      Display and fuses good, but still missing or low voltages.
    If you have checked the fuses, and you know the display itself is good (tested in another game), you will need to rebuild the Dot matrix controller board. Usually it's either or both of the MJE power transistors (the ones with big heat sinks) at locations Q1 (WPC-95) or Q3 (WPC-S and prior), and Q6. If you want to rebuild the entire power sections, here are the components to replace.

    • MJE15030: Q1 on WPC-95, Q3 on WPC-S and prior. Controls the +62 volts. Connects to F601 to BR1 (and D3 and Q2, Q10 and R4, R3, R12 on WPC-S and prior).
    • MJE15030: Q7 on all WPC versions. Controls the -113 volts (connects to Q6 and D6 and R8, R9 on WPC-S and prior).
    • MJE15031: Q6 on all WPC versions. Controls the -125 volts (and -113 volts). Connects to F602 to BR2 (and D4, D5 and Q4, Q5 and R5, R6, R13 on WPC-S and prior).
    • MPSD02: Q2, Q10 on WPC-S and prior. Q2, Q3 on WPC-95.
    • MPSD52: Q4, Q5 on WPC-S and prior. Q4, Q5 on WPC-95.
    • 2N3904: Q1 on WPC-S and prior only).
    • 1N4759 (62 volts): D3 on WPC-S and prior. D2 on WPC-95.
    • 1N4758 (56 volts): D4, D5 on WPC-S and prior. D1, D18 on WPC-95. Doesn't fail as often as the other above listed components.
    Also you will need to check resistor values. They should be within 10% of spec:
    • 4.7k ohms, 5 watts: R8 on WPC-S and prior, R43 on WPC-95. Replace if it looks at all damaged, even if it measures OK.
    • 1.8k ohms, 5 watts: R9 on WPC-S and prior, R44 on WPC-95. Replace if it looks at all damaged, even if it measures OK.
    • 120 ohm 1/2 watt resistors at R4, R5 (WPC-S and prior only).
    • 47k ohms 1/2 watt at R3, R6, R12, R13 (WPC-S and prior only).
    Generally either Q1/Q3 or Q6 will go bad. If either of these fail, both should be replaced(make sure you use white heat sink compound when replacing these, and make sure you have them screwed tightly to their heat sinks). The MJE at Q7 comes after Q6, so it usually survives. Also the smaller switching transistors that are connected to Q1/Q3 and Q6 should be replaced (MPSD02 and MPSD52). Finally the zener diodes 1N4759 (62 volts) should also be replaced. The diode 1N4742 (12 volts, D6, D8 on WPC-S and prior and D3, D5 on WPC-95) generally do not go bad. On WPC-S and prior, check the 120 ohm 1/2 watt resistors at R4, R5 and 47k ohms 1/2 watt at R3, R6, R12, R13. Also check the 4.7 ohms 5 watt and 1.8k ohms, 5 watt resistors. Replace any resistors that are out of tolerence or that appear burnt. Always mount the resistors slightly above the board to allow air flow below them. 

    Cloudy Dot Matrix Display.
    This is usually caused by heat related problems. Fixing this could be as simple as adding new white heat sink compound to Q1/Q3, Q6, Q7. Also make sure they are tight to their heat sink. 

    Wavy Hum-bar in the Dot Matrix Display.
    If you WPC-S or earlier dot matrix display has a "wavy hum-bar", try replacing capacitors C6, C9 and C10 on the dot matrix controller board. These are .1 mfd 500 volt caps that filter the DMD high voltages. If they caps fail, you will get the hum bars. 

    Crystallized Solder Joints.
    If a DMD display is not displaying correctly, and the voltages seem Ok, also check this. It's common for the solder joints on the zener diodes in the power section to crystallize, causing heat damage, excessive resistance, and finally a lost of voltage regulation. This can then lead to a failed DMD and damaged power circuits. These diodes are D3, D4, D5, D6 on the dot matrix controller board. 

    Replacing Q2/Q10 and Q4/Q5 on the Dot Matrix Controller board.
    On WPC-S and prior games, the dot matrix controller board uses two MPSD02 and MPSD52 transistors. More common transistors are available for replacement. A 2N5551 can be substituted for the MPSD02, and a 2N5401 can be used for the MPSD42. 
    Testing DMD Controller

    6.25.12 Failed RAM

    Most failures of the DMD controller that are not attributed to the high voltage section are caused by failed 6264 static RAM at U24. 
    Since the RAM is very susceptible to electrostatic discharge, they are often damaged by improper handling. 
    Sometimes, they just fail. Failure of this RAM manifests in many ways, including some shown below. 

    At the very end of "display test" the MPU performs a read/write test of the RAM. 

    If the MPU is able to communicate properly with the DMD controller, 
    riting to and reading from the 6264 at U6, then the message "RAM TEST OK" is shown on the display. 
    Any other message indicates a failure of the test. 

    Test failure may be due to the I/O buffers on either the MPU or the DMD controller, the ribbon cable, or the actual RAM.

    Note: A YouTube video of a successful display test can be found here. 

    6.25.13 Page Errors

    There are 2 pages of 16 memory locations (0 to 15) stored in RAM on the DMD controller board. In the Display diagnostics it will run the page test and display any possible faults on either the low page or the high page (page 1 and 2 respectively) If you are only seeing errors on page 1, look to change out U33, most likely at least one output stuck high (pins 2,7,10,15). Page 2 errors the likely culprit is U35. Both devices are 74LS175. If you are seeing the same errors on both page tests, most likely it will be U16, a 74LS157, which is the A/B selector between the two page addresses.

    Page errors will also throw up a RAM address error. The RAM is not at fault, just how it is addressed by the page selectors. It should clear after attending to the above

    Note: the coin door buttons for advance/go back can be held down to quickly move through display test.

    6.25.14 Failures of Various Logic ICs on the DMD Controller

    The following images represent various failures associated with specific ICs on the DMD Controller board. Of course, the specific way that an IC fails will influence what is displayed. That is, your mileage may vary.

Pinball The Shadow : How to check a defect Switch 53 Mon(g)ol

Fail on Switch 53 Mon(g)ol target 

What to check
J1xx = Power Driver Board
J2xx = CPU Board
J3xx = Dot Matrix Cotnroller Board
J4xx = Fliptronic II Board 

Switch 53 - Mon(g)ol target
33 Inner Sanctum
43 Through 3

Colum 5, Green Black, J207-5, U20-14 (ULN2803)

Check R72 1K Ohm
Check C16, 470pf
Check U20 ULN2803, pin 14
Check U14, LS3645C, pin 5

On WPC-S CPU boards, the ULN2803 chip is underneath the battery sub-board.
 ULN2803 is equivalent to NTE2018. 
If U20 dies "hard", it could also blow the 74LS374 at U14 
(on WPC-95 it's U23, a 74HC237) on the CPU board. 

Row 3 White Orange J209-3, U18-5 (LM339?)

Check D5, 1N4148
Check C5, 470pf
Check R56 2K? (vergleiche 54)
Check R55 1K
Check U18, LM339, pin 7

Check Diode Playfield 1N4004

Green ---o \o---|<=---white

Testing a Blade/Leaf Switch's Diode.

    Leave the leaf switch's diode and all wires connected.
    Make sure the switch isn't activated.
    Put the DMM on diode setting.
    Connect the black lead of the DMM to the diode's banded side, and the red lead to the non-banded side.
    A reading of .4 to .6 on the meter should be seen.
    Reverse the DMM's leads (red lead to the diode's banded side). A null meter reading should be indicated. 

Nice links

Friday, 10 January 2020

Pinball repair judge dredd rework of light illumination pcb

Everything can happen,

Dirty bulbs
Defect bulb
Ripped traces
Worn sockets
Cold solder points on connectors

Just checked everything

Pinball repair judge dredd Planet gear box motor

Crackling sounds come from the gear box of my judge dredd Planet motor. This part cost 400 bucks replacement part and difficult to source. So I took preventive action to repair it.

First, take pictures of cable connection and parts. Planet needs some steps to disassemble from playfield.

The gear box

Take car of tiny parts. There's no replacement available.