Power Suppy Selections (Pins of J1 and J2)
Power Supply Selection*	J1 (pins 1 & 2)	J1 (pins 2 & 3)	J2 (pins 1 & 2)	J2 (pins 2 & 3)
+/- 12 Volt (Internal, P1)**	Out	In	Out	In
+/- 15 Volt (External, P2)	In	Out	In	Out
* Internal and External Supplies should not be mixed (e.g. do not use +12 Volts with -15 Volts).
** The Board is shipped with the default jumper settings for +/- 12 Volt supplies as shown in the image above.