Long ago I had a part-time job fixing consumer electronics at a small, 
independent retail store.  Bill, the store's owner, did a big business 
in TV sets and appliances like washing machines and refrigerators.  In 
those days, TV sets were 100% analog and were failure-prone because of 
the less sophisticated design and assembly processes of the day, the use
 of high-voltage at the CRT (picture tube), and the limitations of 
vacuum tube and semiconductors of the day.  So Bill pretty much had to 
have a "service department" to repair the TV sets that he sold as well 
as sets that he hadn't sold but that might need repair or (hopefully) 
replacement with a new set.
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