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PP7A is a switching power supply located in a metal box on the left side of the monitor. This picture shows the cocktail table version of Radar Scope and the arrow points to the PP7A located behind the coin box. |
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The 6P ESS and 7P SOU plugs are on the back side of the box. Seen from the solder side, you will have the two GND pins of the 6P ESS on the left as in this picture |
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On the top of the plug you can check voltages by applying the probe during attract mode.
In a working game they were, for example: 4.83 V (low by 3.4%) / -5.07 V / 12.04 V / 23.33 V |
| +5 Volts | @pin |
| 6P-4 | |
| 6P-5 | |
| 7P-6 | |
| 9P-6 | |
| 9P-7 | |
| 10P-9 | |
| 10P-10 |
| -5 Volts | @pin |
| 6P-6 | |
| 7P-7 | |
| 9P-8 | |
| 10P-1 | |
| 10P-2 | |
| 10P-3 | |
| 10P-4 |
| +12 Volts | @pin |
| 6P-3 | |
| 7P-5 | |
| 9P-4 | |
| 9P-5 |
| +24 Volts | @pin |
| 9P-9 |
| Ground | @pin |
| 7P-1 | |
| 7P-2 | |
| 10P-5 | |
| 10P-6 | |
| 10P-7 | |
| 10P-8 |
If you have a defective power supply and you are not willing or able to repair it you can easily replace it by using two switching power supplies, one for the +5 and the +12 volts and another for -5 Volts.
The reason for the necessity of two supplies is that the CLK board with its ECL
logic draws a large current of several amperes at -5V.
The original power supply has the following specs
| +5 V DC | up to 7.5 A |
| -5 V DC | up to 6.5 A |
| +12 V DC | up to 100 mA |
| +24 V DC | up to 200 mA |
The 24 Volts are being used for the game counter and can be omitted if necessary
A very good replacement for the PP7A power supply are two PC power supply units from old PC's. I used two identical Magnetek power supplies which are too weak for modern PC's (only 65 W per unit) but can be used as a Nintendo replacement PP7A without problems
You will have to wire them in the following way:
