DI Y

CIRCUITS

TV SET SALVAGE

Nothing good on TV? Well, there’s plenty of good stuff in a TV. By Thomas Arey

During the late 1950s and early 1960s, electronics hobbyists found a wealth of parts for projects inside discarded television sets. It was considered a point of pride in amateur radio circles to homebrew a transmitter out of a broken “boob tube.” Of course, those were the days of 6146B sweep tubes, big 1-watt resistors, and transformers that would break your foot if they fell off your workbench. Occasionally, if you were really lucky, that scrounged set would turn up a couple of those new transistor thingies.

Technology marches on, and the insides of more modern TVs turn up a very different parts complement, lacking in any “hollow state” components except the picture tube. As a radio hobbyist, I wondered: Is it still possible these days to take a discarded TV and salvage the stuff that radios (and many other projects) are made of?

138 Make: Volume 09

Thanks to a 10-year-old General Electric portable I found on a dumpster dive, I happily found out that the answer is yes.

First, a few words of warning. Do not take a television apart unless you are comfortable handling both high voltages and potentially exploding glass. The power supply in a traditional TV presents 30,000 volts when energized. Even unplugged, the capacitors in the power circuit can hold a charge for months. Also, the picture tube is a large glass vacuum container. If it is dropped or cracked it can shatter into thousands of nasty shards. Wear eye protection and gloves when handling the tube. That said, if you are still ready to own your TV like a true maker, let’s go!

Removing the back of my GE set revealed one large circuit board at the base and a smaller one on the back of the picture tube. A thick red high-

Photography by Thomas Arey