Vacuum Tubes

I remember as a youth, having a vacuum tube radio in my bedroom.  Listening to that primitive radio I first heard Led Zepplin, The James Gang, and other classic rock bands when they were at the top. All this through a small, cardboard cone speaker that could not handle much volume.  But the radio brought its own mood.

When I used it, I wouldn't need to have a light on in the room.  The vacuum tubes in the radio would heat up and glow orange, casting their light against the wall and throughout the room. The nostalgic return of vinyl records completely escapes me. But, I suspect a real or simulated nostalgic return of vacuum tube operated radios and TV's are just around the corner.

Technology changes so fast.  How many things from my generation's childhood are completely foreign to our kids and grand children? Phone booths, rotary telephones, cassette players, phonographs, and other high tech gadgets from the 60's and 70's are now only found in antique shops and museums. For some unknown reason, I remembered my old vacuum tube radio this week.

The last mass produced vacuum tube was the cathode ray tube, or CRT, that was finally retired when flat screens were invented. But before the CRT was the vacuum tube that served as amplifier, power regulator, and signal processor for the now antique televisions and radios.  Back in the day, a general consumer could fix their electronics by replacing a defective vacuum tube.

That was a good thing since electronics built on vacuum tubes were very unreliable. My memory of the family TV was that it was rarely in good working order, and constantly needed vertical and horizontal adjustment to achieve a watchable picture. When was the last time you saw a modern TV exhibit the vertical roll of old TV's?  I don't know if I ever have.  I'm not even sure the new TV's have an adjustment for that picture problem.  Much of this reliability is due to the replacement of vacuum tubes with transistor and integrated circuits.

Vacuum tubes were user replaceable and made many fathers an effective TV repairman.  Grocery and hardware stores had a device where common vacuum tubes could be plugged in and tested.  When the TV set wasn't working, or the picture became unwatchable, my father would open up the back of the TV set and remove all the vacuum tubes. We would visit the store with a tube tester and one by one, plug each into the slot that matched the vacuum tube pin configuration, set the dials as instructed, flip the test switch, wait for the tube to warm up, and read the red-yellow-green meter to determine if the tube under test was the culprit.  If it was, replacement tubes were stored under the tester and could be immediately purchased.

Today, TV sets don't have vacuum tubes and contain no user replaceable parts.  When the TV stops working, we throw it away and buy a new one. Once there was a large number of TV repair businesses.  When did you last seen one?