Solid State 50A1 replacement for the Zenith Transoceanic. This device is fully solid state and uses a modern linear regulator IC set to 53 +/- 1mA. It is designed for the Zenith Transoceanic, but can be used in other radios provided they use the same polarity (pin 2 positive with respect to pin 7). Some radios, such as the RCA Strato-World, use the opposite polarity and will require pins 2 and 7 of their 50A1 sockets to be reversed. Reverse polarity will not harm the 50A1 replacement, but it will not operate until the polarity is corrected.
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