Bally MPU remote battery Q

[Cryptkeeper]

The Black Pyramid I got off bigIan came with the battery removed,
Sometimes (mostly) I cant access the menus after the coil,display & switch test.
I suspect its the lack of batter but eiterway I need to fit a new batter pack.
Is it the same as a doing a WPC ?
3 AAs ?
Any diodes needed or anything ?
Thanks

 

[astyy]

3x AAs plus diode to stop reverse charging yes. The memory/super caps are good and hold charge for months. Scroll down in Clays guide to where it says "New Battery";
http://techniek.flipperwinkel.nl/ballyss/rep/index1.htm#battery

Edit. Settings should work without battery though just not stored.

 

[BigIan]

I can give you a battery saver chip, will need to check if they can be used in a midway first

 

[carl lawrence]

3x AAs plus diode to stop reverse charging yes. The memory/super caps are good and hold charge for months. Scroll down in Clays guide to where it says "New Battery";
http://techniek.flipperwinkel.nl/ballyss/rep/index1.htm#battery

Edit. Settings should work without battery though just not stored.

3 AA is 4.5v ,I always thought it had to be 2AA = 3v plus the diode for these older machine ?

 

[Jay Walker]

Most silicon diodes lose 0.6V across the internal semiconductor junction, leaving 3.9V available from a set of fresh AA cells.

 

[Cryptkeeper]

So 3 batterys or 2!?

 

[pinballmania]

3

 

[Moonbus]

A little hijack...

Am I wrong in thinking that the on board memory chip powered by the batteries can take up to 7v in standard use and the only reason they used the battery configs they did was because they were limited to using the stabilised 5v to charge said batteries?