136603
Stacks of thousands of miniature selenium disks have been used as high voltage rectifiers in television set s and photocopy machine s. Use Radio and television receivers used them from about 1947 to 1975 to provide up to a few hundred volts of plate voltage .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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