Remote battery holder

1 Introduction

There's no excuse for not putting a remote battery holder on any of your late Williams games - System 3 on up. If the battery holder on the board is in good shape - that is you have the batteries there now, here's an easy project that let's you remove the batteries from the board preventing the risk of battery leakage ruining the board.

The no solder approach uses two dowel rods to mount into the battery holder on the CPU board with leads running to the remote battery holder. One of the dowels will go to the negative side (black wire) and the other will go to the positive side (red wire). There's no need for a diode - as far as the machines concered there are three batteries in the holder on the CPU. Total cost is about $5.

NOTE If your game has a charging circuit, you need to add a blocking diode to prevent the charging of the non-rechargable batteries. It doesn't hurt to add a diode. If you get a 4 cell battery holder, you can solder in a diode in the slot for the 4th battery.

2 Parts List:

• (2) Flat top wood screws or sheet metal screws #6 1/2 inch
• (1) 3 place "AA" Battery Holder - Radio Shack sells these.
• (2) 12 inch or longer pieces of 18 to 22 gauage wire of different colors preferable red and black.
• (1) 2 pin connect with two male pins and two female pins OR two wire nuts.
• (3) AA batteries.
• (1) 1/2 inch wooden dowel long enough to cut two 2 inch pieces from
• (2) Ring type wire connectors

3 Tools:

• Crimper or soldering iron
• Screw driver
• Drill and small bit for making pilot hole

4 Construction

1. A double A battery is just under 2 inches long and a 1/2 inch in diameter. The object is for each dowel to be the exact size of a AA battery including the screw and wire connector.
2. Measure the height of the wood screw head and cut the dowel to the correct size yielding two slighly smaller than 2 inch pieces.
3. Using the drill, make a pilot hole in the center of the dowel on one end only. So each dowel will have one end with a single hole.
4. Attach the wire to the Ring type connector (solder or crimp).
5. Put the ring connector on the screw and screw it into the end of the dowel.
6. Repeat for the other dowel.
7. Label the dowel with the red wire POSITIVE (+)
8. Label the dowel with the black wire NEGATIVE (-)
9. Put the two wires into the 2 pin connect connector (skip this if you opt to use wire nuts.
10. Put the two wires from the remote battery holder into the other part of the 2 pin connector making sure that the red wire goes to the red wire (positive to positive).

5 Installation

I would advise you to power off the game! Yes, you will loose your settings so record anything you care about especially the features and adjustments. But if you are brave, go for it and leave the power on.

• Remove the batteries from the CPU.
  Do not have the connector connected - or wire nuts fastened.
• On WPC games all the batteries go the same way - POSITIVE side goes up.
  Take the dowel marked NEGATIVE and put it with the screw side downwards (toward negative) in the left most battery position.
  Take the dowel marked POSITIVE and put it with the screw side up (towards positive) in the right most battery position.
  The middle position will remain empty.
• Put the three batteries in the remote battery holder according to the directions.
  You should have between 4.3 and 4.8 volts between the black and red wires. If you don't either your batteries are weak or your remote holder is not the right type - the batteries are not in series.
• Connect the remote holder to the connector from the CPU battery holder using either the connector or wire nuts.
• Turn on the game - set the date and time and a few adjustments.
• Turn off the game and wait about 5 minutes.
• Turn on the game and make sure it doesn't say factory setting restored or set date and time.
  If it does this indicates that the remote battery holder is not working properly. The first thing to try is to reverse the dowels in the batter holder. ALWAYS keep positive to positive. Just put the positive dowel in the left side and the negagive in the right side. The middle is always empty.
• You can use velco or a screw to mount the remote battery holder in the backbox or you can just leave rest it in the bottom of the backbox.

Here's a WPC game with the remote holder installed.

Here's a System-11 game with the remote holder installer. Notice that + is on the bottom for System-11 games and the plus end goes on the left side.

6 Resources

Mouser electronics sells the battery holder as does radio shack (sometimes!).

If you don't want to build a remote battery holder you can get one already assembled from: ??