Need help with monitor in Japan

Hi A 12v filament transformer can be used to boost the voltage. Also, Japan is 50Hz so that may also be an issue. One could even use an AC wall wart as long as the output current was rated as high as that used by the monitor. You just need to experiment with the lead polarity to get the phase to boost. You'd need to put this all in a closed box for safety because the output wires of a wall wart are not usually rated for 115V. Dwight surprising (especially with a DMM with a high input impedance), resulting from inductive/capacitive coupling between wires over the distance between your measurement point and where GND and neutral are bonded in the building (assuming that Japan does a straight GND/neutral bond as is done in North America). 115V (you don't say how old the monitor is, could it be that it predates power supplies with 'universal' supply voltage range?). Try finding a power adapter transformer to boost the voltage. (Normal Japanese line voltage is lower than North America isn't it?). Or if you are around electronics people, try to find a variac, as variacs typically have some boost on the upper end of their range (for example, a variac fed with 120V will typically boost to at least 130V, keeping in mind if the variac scale is presented in volts, the scale accuracy will vary with the input voltage). (Or, being very careful not to go to the low end, wire up the variac in reverse). jumpers, or alternative primary taps on a power transformer, to select input voltages.