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Maxed Out: In My Day, Part 2
April 18, 2012 |Estimated reading time: 6 minutes
As you may recall, I’ve recently taken to ruminating about how quickly technology has been evolving, and how much things have changed since I was a kid. So, once again, let’s plunge into the fray with gusto and abandon.
Hanging on the Telephone
A couple of columns ago I was waffling on about the days of my youth, when you had only a single rotary phone in your house (if you were lucky). This was, of course, long before the introduction of super-cool things like cell phones and suchlike. Well, the day after this article was posted, reader Phil Carlson e-mailed me to say:
Dear Max,
Your current column in PCBDesign007 really struck a chord with me. I was born in 1952, and we didn't have a telephone until I was in sixth grade, circa 1963. Prior to that, the local small town telephone company didn't have direct dial service. My grandmother, who lived next door, did have a telephone (no dial), and it was on a party line with 3 or 4 other subscribers. We were told that there were not enough phone lines on our road to add us as a subscriber.
Whenever there was a call for one of us (there were eight living in our house), my grandmother would run over yelling that we had a call! When you picked up her phone to place a call, you signaled the operator, who worked the switchboard in the living room of my high school English teacher's home. When you received a call, you had to listen for your ring code, which might be something like one short ring followed by two long rings (to differentiate you from others on your party line). One benefit of this system was that one long ring meant the call was for everyone on the party line so that community announcements could be made.
Around 1963, the local phone company upgraded to dial phone service. We then got our own phone (one phone in the kitchen), but also on a party line. One phone was not adequate for so many people in our house, and extension phones were expensive as they could only be rented from the phone company in those days. Consequently, when I was in high school, I built an automatic PBX (private branch exchange) system from parts I scrounged at local hamfests (including some of the phones). It was implemented primarily with relays and a few transistors to produce the dial tone and busy signal. Each room in the house had a dial phone. When you picked up the phone you heard my dial tone. You dialed a one-digit number to call another room. If you dialed 9 you connected with the outside phone line. If you heard the phone ring in the kitchen, you could pick up your phone and dial 9 to answer it. The system worked pretty well.
My wife and I now have cell phones, of course, but we still also have a land line in our house, although it's a VoIP system (Vonage), which allows us to take the Vonage box back and forth between our two homes (we're snowbirds). That way our phone number is the same regardless of where we are at the time. It sometimes seems incredible to me to have gone from no phone service to all this in less than 50 years.
Phil, who is obviously a very clever and discerning fellow, closed by saying, "By the way, don't tell the folks at PCBDesign007, but many times I only read your column and don't take time for the other articles." Well, of course I am known as the soul of discretion, so my lips are sealed (grin).
Twiddling with Knobs
I followed my column on telephones with a counterpart on televisions. I forgot to mention how temperamental the old televisions were, and how you often had to twiddle and fiddle with their knobs to make them work at all.
Today’s flat-screen televisions are incredibly sharp and bright. The technology used by the displays means that the picture appears in its entirety when the television is powered up. This contrasts with the old cathode ray tube (CRT) displays, in which the picture started off small in the middle of the screen and gradually grew to fill the screen as the set warmed up. Similarly, when you turn a modern television off, the picture instantly disappears. By comparison, when you flicked the OFF switch on a CRT-based television, the picture would gradually shrink towards the center of the screen until nothing was left but a bright dot, which then faded away.
Another aspect of modern television displays is that they are also incredibly reliable in the grand scheme of things. This is largely due to the fact that they are based on digital electronics. By comparison, the TVs of my youth were based on analog systems that were very carefully balanced. The problem was that things began to deteriorate over time. After a few years the component values might start to vary slightly, resulting in all sorts of weird effects.
For example, your picture might shrink in the horizontal direction such that it no longer fit the screen. Or it might shrink in the vertical direction. Or it might start to move such that the upper portion of the picture disappeared from the top of the screen and reappeared at the bottom, so you might be watching “I Love Lucy” where her head and torso were at the bottom of the screen and her legs were walking around above her.
If left unattended, the image would start to rotate from top to bottom, or vice versa, which was a bit like watching one of the dials on an old-fashioned slot machine just after you had pulled its handle. In order to address this, on the back of the set there would be a collection of knobs that allowed you to adjust the width and height of the picture, and to move the entire picture up/down and left-right.
The problem was that once you started playing with these knobs, you were doomed to keep on tweaking and tuning them henceforth. Actually, I was just talking about all of this with Andy Shaughnessy, our esteemed leader at PCBDesign007. Andy said that when he was a kid he had crawled behind their family TV, and he had always wondered what the knobs with esoteric names like “Vert. Hold” were for (you wouldn’t have dared to touch them, of course).
Andy also noted that televisions at that time were so expensive that you did your best to keep them going as long as possible. He remembers when the channel changer knob broke on their family TV, and his father took a pair of vise-grips and locked them into place on the metal rod controlling the switch. They used the vise-grips for several years until that TV finally “gave up the ghost.” (I once borrowed these vise-grips and lost them, leaving us stuck on the same channel for two days. --Ed.)
These days, televisions seem to keep on working forever. And if one should fail, most of us think nothing of tootling off to the local appliance store and picking up a replacement – a far cry from the day when a television cost the equivalent of several months’ hard work.
Until next time, have a good one!
Clive (Max) Maxfield is founder/consultant at Maxfield High-Tech Consulting. He is the author and co-author of a number of books, including Bebop to the Boolean Boogie (An Unconventional Guide to Electronics) and How Computers Do Math featuring the pedagogical and phantasmagorical virtual DIY Calculator. To contact Max, click here.