Defender/Stargate PSU

[spacies]

Hi,

Does anyone have info on converting a Defender/Stargate to use a switchmode PSU?

Any links or info appreciated.

 

[RetroACTIVE]

Here is a pretty good place to go for Williams stuff.  Requires a little read but it is complete.

http://www.robotron-2084.co.uk/techwilliams2jamma.html#power

[spacies]

Thanks,

Does it require a battery change to use a switcher? I read somewhere about changing to lithium batteries?

What about the -12V from the original loom?
Switchers don't have those.

[RetroACTIVE]

Does it require a battery change to use a switcher? I read somewhere about changing to lithium batteries?

Nope... the battery is for CMOS memory retention when power is off.  Its a separate circuit all together.  Changing the batteries to lithium is a good thing to do anyway.

What about the -12V from the original loom?
Switchers don't have those.

Some switchers do have -12V... usually ones that are > 150W.  But I don't think its a problem
This is what it said @ http://www.robotron-2084.co.uk/techwilliams2jamma.html#power 
"The Sound board requires +12v unregulated, -12v unregulated and ground. The +12v and -12v are rectified on the sound board to produce its own regulated +5v supply. If you use -5v and +12v from the JAMMA PSU it will work fine."