The Tubes

So, what did you do when the TV stopped working??

- Take it to a TV repair shop - naw - too expensive!

- Joggle it by slapping it upside the head.

- Turn it on and off.

- Adjust the antenna (rabbit ears).

- Turn it off and let it cool down.
- As a last resort, pull out all of the tubes (vacuum tubes), take them to the nearest convenience store (except they didn't call them that back then - they were convenient enough, but they were just small corner stores). You could also take them to the supermarket.

At the corner store or supermarket, you would usually find a tube tester - with shelves in the cabinet under the tester where new tubes were stored.

All of the black spots along either side of the main panel are sockets where one-by-one you would plug in a tube. In the center at the top of the panel is a meter. As the tube would warm up, the meter would indicate the health of the tube. The three black things under the meter are dials that had to be set according to the exact part number of the tube to be tested. A tube directory was on hand to indicate which socket was to be used and what the settings of the dials needed to be.

After determining the health of the tubes, you would purchase one or more new tubes as necessary, go home, plug them all in (hopefully remembering where they came from), turn on the TV and it would usually work.

Three vacuum tubes are illustrated below. The one on the left is an 807 tube. My dad used to use these in building radio transmitters. The other ones are representative of what you would find in an old TV set. Most of them were smaller like the one on the right.

I hope this helps - take care,

roy

The Vibrators

So, since I am a bit older than most of you, here goes. OK a lot!
Back in the 40s and 50s, the first thing you would hear when you turned on the car radio was a humming sound. You would hear it usually until the radio warmed up at which point you would hear the music or whatever. If at that point you turned the volume clear down, you could hear the vibrator again unless you were driving fast with the windows down.
Now, the whole radio didn't need to warm up, but the tubes had to warm up and that required high voltage. The car batteries back then were only 6 volt (but even if they were 12 volt, it wouldn't matter).
So ... there was a vibrator that would vibrate. The vibrating part had electrical contacts on it that would make and break contact with each vibration. From the 6 volts of direct current (DC) that the battery was supplying, this action would create pulsating direct current. That electrical current would then pass through the primary windings of a transformer which would create alternating current (AC) at a higher voltage in the secondary windings of the transformer.
Then, this higher voltage AC was used to power the tubes. The tubes did some of the main work of processing the radio signals from the antenna into audible sound. There was a filament (like in an incandescent light bulb) that would heat up and glow red inside the tubes.
Then along came semiconductors (transistors and then, integrated circuits, etc.) and the demise of the vibrators and tubes.

If you want some vibrators, here they are:


Only 9 bucks for the set. Just go to cgi.ebay.co.uk. Who knows?

More about the tubes later.
Love,
me