Adding Set-Top Box To Your TV Is Nothing New
By bohus
Today there's a battle raging for the top of your TV set - metaphorically speaking. it's no longer enough to just have a television. You need add-on hardware to bring your TV additional services like cable and even the internet. I find the continued use of the term "set-top box" amusing since new televisions are far too narrow to balance anything on anymore.
There are plenty of new media moguls duking it out for this new bit of media real-estate (along with the genuine real-estate in your entertainment center), but this battle isn't as cutting edge as many might think. In the 70's and 80's, cable subscribers received set-top boxes that were additional tuners to bring in all of those snazzy new cable channels, and even decode the special shows that only *ahem* ran after dark. That's not the beginning either. Set-top boxes go back even further, almost to the earliest days of television.
Early TVs had VHF tuners that could only receive channels 2-13. It didn't take long to see that this TV fad was going to stick around for a while, and that there was a genuine need for more channels. The only way to create new channels was to broadcast on the UHF band. The problem for these new broadcasters was that TV's weren't required by law to build in UHF tuners until the All-Channel Receiver Act of 1962. So TV fans had to rely on external UHF converters like this unit from Johnson.
This is frankly a cheapie. Dark plastic with swirled in colors to give a vaguely woodgrain effect. Earlier units were actually quite lovely, some Bakelite beauties have the good look of classic radios (check out this awesome collection), but not my Johnson. This workaday unit was set up to pass the VHF signal, until you turn the serious-looking UHF knob on. You tune the channels via the control on the right which oddly enough does not click between channels. You just have to slide it into place and hope for the best. I imagine a lot of knob twiddling to get the reception just right.
I don't know the year of this particular converter, but I do know that UHF converters were still available into the 1970's if you were still stubbornly holding onto your VHF-only TV. Of course for those of us still watching TV on CRT televisions these days, we all had to get our own external set-top tuner boxes to benefit from the digital broadcast changeover. When we did, we joined a long history of external TV upgrades that are almost as old as TV itself.