I designed and built this (generic) external battery box for my DE LW3 game
last autumn at more or less no cost at all.

http://pinside.com/pinball/forum/topic/dataeast-leathal-weapon-3-lw3-missing-chip
(Battery box build images is a few posts down)

I learnt that there are a few things to keep in mind when doing this mod.

1. The battery boxes one buy are pretty cheaply made, so some minor adjustments
may need to be done to get a snug fit of the batterys and the right (4.5v or so) voltage out.
Use a multimeter to measure!

2. The polarity of the current from the external battery box of course need to match the polarity
points on the soldered battery box. Use a multimeter to measure!

3. Pay attention to the soldering points of the original battery box. How is the serial current routed
to the main board. Use a multimeter to measure what soldering points give the 4.5v while batteries
seated in original battery box. Different manufacturers have different solutions.

At first I did not pay any real attention to point 3 in my mod, (and it resulted in memory loss since
I only outed approximately 3v). I found that the DE pins (always? help me out here guys) use the
two lower right soldering points of the battery box to lead the current on to the main board. And the
other manufacturers uses a other set of soldering points to to the job.

Thanx for reading
/mima

_{Post edited by mima : cross thread linking did not work as I thought it would}