I have an idea for a power supply/charging system for any portable. It is an "upgraded" version of the circuit Ben has for the CNC SNESp in his book. Instead of only being able to charge the batteries while the unit is off, why not make it so you can charge them when you are using the AC adapter? All you need is a DPDT momentary pushbutton switch
and any jack from RadioShack (I like this
type because in the case of a portable PSOne, you can use the original power cord in an unaltered form.)
30 minutes later...
This is a schematic of the circuit:
You will need the above items, and:
a DPDT switch (doesn't matter as long as it's DPDT)
a charge plug (as described in the book for the CNC SNESp)
drill/ 1/8" bit
spare piece of 1/8" thick stuff (doesn't matter as long as it's sturdy)
1. Using the drill, put a hole into the power jack (not all the way through, just into it). Also be careful not to destroy the outside (ground) contact as you will be using it. (fire up the glue gun and soldering iron too)
2. Slice off the corners of the button on your momentary DPDT switch until it fits in the hole. Bevel the top at a 45 degree angle.
3. Solder a wire from the positive terminal of the batteries to one of the center poles of the DPDT momentary switch, a wire from the pole adjacent to it (the other center pole) to the battery wire's side NC pole and a wire from there to a center pole on the DPDT power switch. Solder a wire from the NO pole (the same side that has a wire going to its NC pole. Then, solder a wire from the other NO pole to the tip of the DC AUX jack. FInally, solder a wire from the negative battery side to the other center pole on the power switch. Use the schematic to help you through this.
4. Ok, time to finish soldering! Solder a wire from the positive side of the charge jack to a side pole on the positive side of the power jack. Solder a wire from the negative side of the charge jack to any negative wire nearby (preferrably the one going to the power switch, there is a mistake in the schematic too, the wire should go to the negative going into the switch, not the other pole). Solder one wire from the terminal on the positive side and the pole on the negative side. These are the wires that power your portable. You should have 5 poles connected on each switch.
5. Glue the DC AUX jack onto the sturdy stuff with the hole on the side (not the top or bottom). Take the adapter that is going to power the device and stick the plug into the power connector. Then, insert the pushbutton switch so it turns on. Hold them in place on your sturdy piece of stuff and remove the plug. If the switch pops back when you remove the plug, you're in good shape. Hot glue it in place exactly where it is.
Check all your connections with the schematic. I will eventually make a diagram for wiring the switch, but until then, get someone who knows how to read schematics well and try your best. Definitely check twice because you could fry the portable or blow up the batteries if it's wired wrong.
Edit: Wiring Diagram!