DC Polarity Checker & Symbol Decrypter
Connecting a reversed polarity adapter will destroy electronic circuitry in less than a second. Use this tool to match the symbols printed on your device and adapter.
1. Target Device Socket
What the gadget expects2. Power Adapter Brick
What the adapter suppliesHow to Verify Polarity with a Digital Multimeter
Turn the multimeter dial to DC Volts (⎓ V or VDC) at 20V range. Plug the power adapter into wall AC power.
Touch the RED probe inside the hollow center pin and the BLACK probe against the outside metal barrel.
If the screen shows +12.0V (positive), it is Center Positive. If it shows -12.0V (minus sign), it is Center Negative.
Need to invert polarity for guitar pedals?
If your adapter is Center-Positive and your pedal requires Center-Negative, you can use an inexpensive DC Polarity Reversing Adapter Cable instead of buying a new power supply.
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