Television

Television


In the 1950's Al Botcher brought home to the farm the most awesome, cutting-edge device of the day.  He purchased a television set.  For the benefit of my grandkids I have to describe how the earliest televisions worked because they are a totally different animal from the ones we have today, just as the telephones were.

Television as we know it today is digital technology.  It relies upon millions of tiny computational gates printed upon chips.  The picture is really constructed of little pixels, or light-emitting diodes, connected to these chips.

The television that Al brought home was a completely different animal, much like we are a completely different animal when compared to our predecessors the apes.

Our new TV was a big monstrosity in a wooden cabinet as big as a clothes dryer.  It had to be in a big cabinet because instead of a wonderful rare-earth flat screen, it mainly consisted of a picture tube, the front of which was the "screen" that we looked at, and the rear of that tube extended back into the cabinet about two and a half feet.

The rear of the picture tube funneled down to about the diameter of a pop bottle in back and wrapped around it was a "yoke" made up of many, many windings of copper wire in the up-down plane and in the left-right plane.  The whole thing was called a cathode-ray tube.

The idea of the cathode-ray tube is that the little base in back fires a stream of electrons right at the middle of the front of the screen which is coated with a material that absorbs a certain portion of them and fluoresces.  The picture to be shown to us is scanned by a camera that amounts to the opposite of the television.  The brighter part of the picture scanned causes a stronger radio signal, which the TV set intercepts and causes a correlating increase in the amount of electrons fired at the middle of the screen.

But it is of no use to us to have all the information mashed into one point in the middle of that great big screen.  That is what the windings are on that yoke in back.  Electricity is also fed through these windings.  Electricity and magnetism are the same thing in a certain sense, so the current travelling through the windings creates a magnetic field.

In the back of the TV and taking up a lot of room are a couple of aluminum chassis, like rectangular upside-down boxes.  Several more electron tubes are mounted on this chassis along with a lot of other hardware that isn't even used in TV's anymore, but was necessary in the early ones.  All of these things, resistors, capacitors, coils, chokes, transformers, and such were wired and soldered together to make a circuit that caused the stream of electrons to be deflected in a very specific manner by the strength of the magnetic fields created by the current in those windings on that yoke.

The beam of electrons scans the surface of the front of that tube and paints a path across it, drops down an ever-so-slight amount, and paints a path back, repeating this until it gets to the bottom of the front of that tube.  Then it goes to the top and starts over.

This happens many, many times per second.

All the while, the strength of that beam fired from the back of that cathode-ray tube by the "electron gun" is varying with the lightness and darkness of the picture that they wanted us to see.  All this is going on like a foaming froth on the front of that picture tube and the only reason we see the picture at all is that when our eyes are stimulated, the image stays for a quarter of a second before dissipating.

It's a wonder that the whole mind-boggling idea even worked at all, but it did.  All we had to know was how to adjust two parameters of the process.  There were two knobs, one marked "horizontal hold" and the other marked "vertical hold".  What these knobs did was to make tiny adjustments of the speed at which the windings on the yoke of that cathode-ray tube deflected the stream of electrons.

If the vertical hold adjustment was a little bit off, the picture would roll from up to down on the screen.  As you slowly turned the knob the rolling would slow and when you had it perfect it would lock in place.

If the horizontal hold adjustment was a little bit off, the picture would be torn into pieces from left to right and would look like a bunch of nonsense.  As you slowly adjusted the knob, suddenly it would shift into coherence and look like what it was supposed to.

There were contrast adjustments, which simply made the whole picture lighter or darker to your visual preference.

So far we have been talking only about the picture!  The sound had to be processed by the set as well.  Upon another chassis inside that thing was built, out of all these crazy vacuum tubes and components, a radio receiver.

The picture signal came on one frequency and the sound came on a completely different one.  The radio simply played to go along with the picture.  That was all handled at the transmission station, and there were standardized pairs of frequencies assigned to each channel.

When you turned the switch on, nothing happened right away, just as in the case of my mother's kitchen radio.  The tubes had to "warm up".  Their cathodes had to heat up enough to begin firing a steady stream of electrons.  Then all the little devices within them would function to process the signal.

You would look at the blank screen, waiting for something to happen, when suddenly a small dot would appear somewhere, ripple, and quickly expand to an entire picture.  At about the same time there would be a humming sound.  Suddenly the radio inside the TV would start babbling away and you were off to the races.

Al's new TV was a Motorola and it truly was a marvel.  Black and white picture, of course.  It would be a while before they figured out how to do color and that entails an unbelievably complex bunch of gadgetry and some more frequencies, several years in the future.

I now had some entertainment as I waited long after dark for Al and my mother to arrive home from work and perhaps grocery shopping.  There were certain shows, many of them cowboy shows, provided on different evenings, just as there are today.  Paladin, The Rifleman, The Virginian, The Big Valley, Daniel Boone, Davy Crockett, Gunsmoke, The FBI (Just the facts, ma'am, just give me the facts), Sugarfoot, and the list goes on and on.

There were also movies, boxing matches, the news, and Lawrence Welk and his Champagne Orchestra.  Ronald Reagan was an actor then, not the President of the United States, and he would introduce the movie of the night.

Each program had it's theme song and you knew you were missing the program if you heard it blaring away.

Cable TV had not been invented.  Once in a while you would hear the idea of "pay TV" floated and people would say, "no way!"  A major city usually had a channel and La Crosse, Wisconsin had Channel 8.  Their call sign was WKBT.  But Al had to have an antenna to receive the signals.  In La Crosse you would have been able to get away with having a set of "rabbit ears", a V-shaped antenna that just sat on top of the TV or a nearby dresser or bookcase and was wired into the back.

Pfeffer Valley, however, was hidden between sets of high ridges and we had to have an antenna on a short mast on top of the house, and it had to be pointed in the direction of La Crosse, which was pretty much east.

Eau Claire, which was more north, had a channel, WEAU but you had to physically turn the antenna to point more north before it would come in.  We were pretty much stuck with Channel 8 because the ridges were high and La Crosse's transmitter was on a tower up on one of them.

Electromagnetic radio waves can bounce off large objects like rock cliffs, so there was always some part of the signal getting into the nooks and crannies of the land unless you were really isolated or down in a hole.

I watched TV in the evening and when my favorite couple of cowboy shows were over and they played the theme music, I would leave the TV on because otherwise I was afraid of being alone in the dark.  A lot of the material they showed in the movies was scary and after being sensitized by them, the sound of a raccoon scuffling on the concrete step outside sounded like an axe murderer sizing up the door before breaking it down.

The TV could go on the blink and stop working.  If you were lucky it was one of the ten or twelve tubes.  You took off the back, pulled out the tubes and took them to the hardware store where they had a tube checker.  Tubes had usually nine wire pins on the bottom but there were different sizes of them depending upon the amount of current they had to deal with.

The tube tester had several rows of sockets.  The tubes had their identifying numbers etched into their sides.  They were numbers like 6V6, 6AQ8, 12BA6, 12BE6, and so forth.  There were hundreds of them.  Some of them were amplifiers, some were rectifiers, they all did something to the electrical pulses that were going through the receivers.  You plugged the tube into the socket the little book listed and a meter pointer told you whether it was functioning properly or weakly, or not at all.  A new tube, which cost a couple of dollars, would fix the problem.

There are lots of other things that can go wrong and anything deeper required the TV repairman.  There were people that made a good living just repairing radios and TV's.  You could bring the set in or they would come out and service it right in your home.  They had a van with all the testers, most common tubes, and other common spare parts.

Nowadays the TV stops working and we throw it out, buy a new one at WalMart.

The TV stations did not run around the clock like they do now.  The government made them shut down at night because a strange thing happens after dark.  The ionosphere, one of the topmost layers of the atmosphere has been broiling in the sun all day and the atoms in it become ionized, which is why they call it the ionosphere.  The electrons of the atoms have been absorbing energy from the sun and are stimulated into more energetic orbitals in their atom.

At night the ionosphere would "cool".  The electrons would drop down into lower energy orbitals and the whole ionosphere would shrink a little bit and become less transparent to our radio signals, which had been going right on through it into space.  At night, when the ionosphere becomes more opaque, these signals bounce on it.

The government runs a lot of radio operations and there is quite a competition for "bandwidth" because there is only a finite amount of it, before everybody's radio signals start crowding one another.  So at night, when the signals are likely to skip and go farther, they are likely to interfere with other important signals, so the government made stations sign off in the evening.

They still do this with AM radio, only they only make them reduce power from perhaps ten kilowatts to a hundred watts.  If you listen, even today, to an AM station towards evening you will hear it suddenly become extremely faint.

Certain frequencies are much more likely to skip and in the old time television, it was the frequency that the sound came in on that was the worst.

When I was a boy in single-digits of age, watching the cowboy shows, I had absolutely no idea that all this stuff was going on in that television set.

I just figured it was some kind of magic.