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Using Plug-and-Play? Don't Shrug or Pray

You might not have noticed that equipment doesn't always work. That's actually a good thing, not a bad one. No, this ain't my idea of an April Fool's Day joke.

Maybe you have noticed the part about equipment not always working. Any time you think someone has made a foolproof system, take a gander at the Grand Canyon. If a trickle of water can do that, you ain't got a snowball's chance in a megawatt transmitter of getting through life without something popping on you.

If you've got a redundant system, you can be sure that whichever unit is on the air is the one that'll fail. If you've got an automatic switchover system, count on the automatic switchover breaking. Got dual power supplies feeding a diode bridge? The diodes will fail in a way that'll get you.


In the hazy mists of what was once my memory (one working neuron named Nellie), I seem to recall a show in my youth when a clipped piece of wire landed between signal and ground at the very moment the countdown to live transmission reached zero. A mentor came by to cheer me up after I'd found the malicious metallic millimeter. "Equipment knows when it's on the air, kid."

Now then, there ain't any doubt in what's left of my mind that equipment has gotten better. Back in the days of tube-based amplifiers and cameras, we'd be popping those glass heaters in and out on a daily basis. Cameras and monitors needed to be adjusted at every opportunity. Editing videotape with fluid, microscope and blade approached the complexity of brain surgery, and I ain't entirely sure from which direction.

So, yes indeedy, I'd much rather have today's equipment. But, no offense, I'd rather have it with the training we had in the old days. Case in point: bars and tone.

Color bars were invented for setting up composite-color encoders. I figure a bunch of you are thinking, "What does 'setting up' an encoder mean?" Maybe some of you are wondering what composite color is.

Anyhow, I won't dwell on bars. Tone is bad enough.

Tone, in case you ain't noticed, is, pretty much by definition, one amplitude of one frequency. As a convenient level at which to set a reference, it's fine. But that's just about all it can do. Back in the old days, we knew that, so we ran both frequency and amplitude sweeps. We also knew that FM emphasis would boost high frequencies one whole heck of a lot, so we compensated (if you don't understand this sentence, look up "preemphasis;" it'll be a worthy part of your education).


These days? Well now, I was asked a while back to check out a plant. Tone stuck in one end came out at the same level at the other end—unless you boosted its level a bit. Then it clipped. The engineer who put the facility together wasn't bad but hadn't been educated about peak levels and headroom. The analog-to-digital converters seemed to work fine right out of the box, so no one bothered to check the settings for reference level.

The place had some stereo synthesizers, too. When one of them was bypassed, there was about a 10 dB imbalance favoring the left. When another was bypassed, just about as much imbalance favored the right. No one had educated the engineer about how that type of stereo synthesizer worked, sending some frequencies to one channel and others to the other. Single-frequency tone went one way on one and the other way on the other, and gains were "adjusted" so the system was "balanced," which really meant they were wildly misadjusted to create a huge imbalance. But everything "worked" right out of the box.

Did I mention how we used to slave to get color right on old monitors? Nellie says I did. These days, you just flip on the old LCD, and everything's great.

Now then, I ain't going to get into the contrast ratio or color gamut or even vertical viewing angle of that there LCD. I'll just ask a simple question. Before you bought it, did you ever feed it black?

If you've ever done shading—er, painting—um, if you've ever tried to match the color on two or more cameras (even those delightful, modern, chip-based jobbies), you know that one of the toughest things is to get the blacks properly color balanced. So, having a monitor that can display a nice, flat, purely black black is pretty important for that purpose. But I digress.


Nellie made me write at the beginning of this sorry excuse for thoughtful opinion that all equipment eventually breaks. But that's okay. That's why we humans hang around, to notice the failure and do something about it.

Folks say practice makes perfect. I don't know about that, but I do know that back when equipment went on the fritz all the time, we got a lot of practice at noticing problems and fixing them.

When you know an amplifier is bound to fail, you keep a spare amp handy, you know how to patch the inputs and outputs quickly, and you keep your eyes and ears alert to the first signs of failure. When everything "works" right out of the box, you get a little complacent about spares, labeling and training. Maybe today's equipment works better than the old stuff did, but it seems to Nellie and me that we see more down time than we used to.

When you know a color monitor is going to drift, you check its calibration frequently against a reference. When you think the monitor is fine right out of the box, you end up airing yellowish (or insert your favorite color here) pictures on account of the monitor being too blue (or insert color complementary to your favorite color here).

Yes, I know the economy is tough, and training costs money. But everything breaks.

Mario Orazio is the pseudonym of a well-known television engineer who wishes to remain anonymous. E-mail him