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Many quality radios have the little symbol on the socket denoting tip polarity, and a 'backplate' (mostly) has an input requirement. MAKE SURE THE A/C ADAPTER HAS AT LEAST THE MINIMUM CURRENT REQUIREMENTS (ie 500ma, 750ma, ect) I would take the above suggestion on the swappable tip polarity and then place a piece of tape on the reversible connector so someone doesn't accidentally switch it down the road. Searching the internet for an owners/users manual it best, as well. Have fun!
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