Always wear safety glasses when working n'ear an exposed video picture tube
Place a large mirror so that you can see the screen display from the back of the video module, or else have an assistant watch the display and describe it to you as you adjust the monitor. Plug in the power cord and power-up the game; let the monitor warm up for 15 minutes. The first diagnostic test (crosshatch pattern) will appear on screen. Adjust the focus and vertical size controls against this pattern (see Figure 15 for control locations). If the monitor needs convergence or linearity adjustment, consult the manufacturer (TEKNIKA ELECTRONICS CORP . Service Center. Gothic Plaza 333 RTE 46, Fairfield NJ 07006 — Phone (201) 575-0380, (800) 221-2106), or contact Exidy Customer Service, 390 Java Drive, Sunnyvale CA 94086.
Press ihe laser fire button to bring on the second diagnostic test (color bar pattern).
a Adjust the interface pot it necessary, until there is one black stripe between each primary color b. If retrace lines appear on the screen, turn the interface pot back slightly.
c. Adjust the pot until the screen shows eight steps each of red, green, blue, and grey (counting the vertical black stripes as the first step of each color). The bezel may hide the last two steps of the grey display; if so. just use the ones you can see.
d. If the color is weak, or if you can't get eight distinct steps of each color, adjust the color cutoff pots on the neck board (see Figure 15).
e. As a last resort, adjust the screen drive pot on the neck board (see Figure 15). Use this pot together with the interface pot — when you turn one of them up. you must turn the other down. Note that the screen drive control effects the entire color alignment, if you adjust this control, you will have to begin the color adjustment over again.
When you finish the adjustments, put the game into the attract mode (switch 8 OFF. and resistor R3 enabled). Check the colors of the attraction display (see above. Color Monitor Adjustment, General). It the colors are correct, put some seating varnish or RTV glue on the interface pot. to hold it in place.
Replace the cover of the monitor (reverse of step 5 above), and secure it with its four screws.
1. PICTURE TUBE
2. NECK BOARD
3. SCREEN DRIVE
4. RED CUTOFF
5. GREEN CUTOFF
6. BLUE CUTOFF
8. VERTICAL SIZE (HEIGHT)
9. VERTICAL HOLD
10. HORIZONTAL HOLD
11. INTERFACE POTENTIOMETER 1Z. RED DRIVE (DO NOT ADJUST) 13. BLUE DRIVE (DO NOT ADJUST)
FIGURE 15. TEKNIKA MONITOR, ADJUSTMENTS
F. Main RAM Test, Full Version NOTE
The full version of the main RAM test should be done by a service technician.
With the game in test mode (switch 8 ON), the sixth diagnostic test will normally check 7/8 of the game's main RAM (all but the scratchpad RAM). If you suspect the RAM is malfunctioning, but the normal test does not show anything wrong, you should consider the full ver sion of the test, which 103(3 all the RAM, including the scratchpad To do the full version, you must first disable the Non-Maskable Interrupt (NM1) signal lo the CPU; do this when the game is in test mode, since it cannot enter test mode without the NMI signal.
To disable the NMI, open jumper J6 on the mother board (at location 4G, just below the CPU). We recommend you replace J6 with a switch or test clip before starting the tests. Once m test mode, open the switch or remove the test clip; then bring on the sixth diagnostic test (main RAM) by pressing the laser fire button five times. Be sure to re-enable the NMI when you tinish the test.
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