Resistance is futile

"The goal of all inanimate objects is to resist man and ultimately defeat him." -- Russell Baker

Back to the phone couplers this morning, with a renewed sense of urgency: one of the old ones apparently died this morning. I say apparently because when I tried it, it worked repeatedly without fail -- but the live truck operator who brought the report insists that it wouldn't answer. This isn't a terribly unusual phenomenon, but the problem lies in discerning whether it's a case of intermittent equipment putting on a good face for the person trying to troubleshoot it -- playing alive, as it were -- or a case of someone who doesn't like to do live hits looking for a reason not to.

Anyway, I brought out the big guns to figure out why the new circuit doesn't quite capture the phone line: our 1968 vintage Tektronix oscilloscope, which took up most of the remaining space in my office. After about two minutes of probing around, it turned out that part of the logic was never quite getting up to the necessary voltage to trip the switch. Which is odd, since that part of the circuit is just two resistors. The simplest of parts, which hardly ever fail unless you set them on fire.

Or unless you can't see straight.

Resistors come in hundreds of different values, identified by several narrow colored bands on the side. Different colors denote different numerals: black is zero, brown is one, red is two, orange is three, and so on. So the 3,000 ohm resistor that's part of this simple circuit would have an orange band, a black band, and a red band (to indicate two following zeroes).

Except that this 3,000 ohm resistor actually measures 1,000 ohms. With good reason. What I thought was an orange band is really an unusually cheerful shade of brown.

So I'm not sure whether to be glad at finally solving the mystery, or to be annoyed at the latest proof of advancing age.

"Damn your eyes!"
"Too late..."
-- Young Frankenstein