If you have access to a car battery charger or other 12 volt battery source, you can twist the 12 volt memory and accessory wires together (yellow and red) and attach those to the positive voltage source. Connect the ground wire (black) to the negative source. This will allow you to turn on the unit. Now, you need to have a sound source, and at least one small speaker to test with. Use a CD (simplest) or USB stick with music, or bluetooth enabled phone, whichever will work with your radio to provide music. If you have a bookshelf stereo speaker, or even an old speaker from an alarm clock that should work fine. With your radio powered on, music playing, volume turned up to a moderate level, touch each of the radio's 4 speaker channel's wires to your speaker and make sure you hear sound. If you don't have a car battery charger handy, you can also use an electric drill battery but be sure you know which battery terminal is positive and which is negative before you connect your radio. Another source of 12 volt power may be any number of power adapters that plug into an AC outlet, but you will need to proceed with caution. Check the back of the outlet and note the DV power output, as well as the current output (measured in amperes, or denoted with "mA" or "A". You will need a few amps (not milliamps) to turn on the radio, and at least 12 volts. You'll have to cut and strip the wires, so it's important to know which is positive and which is negative before connecting your radio to the wires. Again, please exercise extreme caution. Do not short the wires together or connect them to your radio in reverse once the adapter is plugged in. Do not perform ANY wire work while the adapter is plugged into the wall.
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