more, lots of PT-100 users long long ago and for decades did MODS.and the power pack mode was 2 ways or both ways1; wired center pin on some CASIO IS WIRED PER PHOTO BELOW. IF USING WRONG PACK IT BLOWS UP THE MOBO.2: added series diode 1N4001 up , to make it never blow up again. (voltage to high still will)I have a mod for #3 , too much voltage using zener diode and a fuse. ask.I have endless ideas on mods for most things that (plug in)the AD1 PACK MISSING AND WRONG PACK USED BURNS THIS KBD UP, AS VAST FOLKS IN THE NET TESTIFY.WRONG PACK OR CLONES SOLD WRONG, I SEE MANY SOLD THAT SHOW AD1 COMPAT, BUT IS A LIE.THEY LIE. NOW.WRONG VOLTAGE SOLD . WRONG POLARITY SOLD AND USED.WIRED WRONG, PACKS.THE PACK IS CALLED CASIO, AD1 (TOLD IN THE USERS MANUAL()MINUS -7.5 VDC AT 2.2WATTS (WATTS BE HIGHER IF YOU WANT)AMPS IS 0.133 amp max or 130mA , I bet the electronics inside uses 100mA max or less..