Sony CFM-31 Portable Radio Cassette Recorder Manual | HiFi Engine
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File:Vintage Sony Model 2R-31 Solid State 6-Transistor Radio, Broadcast Band Only (MW), Made In Japan, Circa 1964 (15947325157).jpg - Wikimedia Commons
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Amazon.com: Sony SRS-XB31 Portable Wireless Bluetooth Speaker, Black (SRSXB31/B) : Electronics