Shown here from fifty years ago, in the November 1974 issue of Radio-Electronics, is an ad for an industry that probably had about ten more years of life. These ads were surprisingly common. They offered re-built (or brand new) tuners from Televisions. If the old tuner went bad, rather than the local serviceman fix it, they could send it in for a replacement, and the one they sent would be re-built. It simplified the repair, and put it in the hands of someone who specialized in that task.
Almost every magazine had one of these ads once a month, so it must have been a profitable industry. But in a few years, solid-state sets, especially with digital tuners, would put an end to the industry.