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As I understand it, the sound of a car's turn signals is that of an electomechanical relay. Current flows through, heats a coil, metal expands, TICK, a leaf switch pops off its contact. The coil cooks, metal contracts, TOCK, the leaf switch snaps back down where it was, and the light comes on again.
So why do car manufacturers use such a piece of vacuum tube cleverness in modern cars? The answer is, at least usually they don't. Turn signals tick-tock because people expect that noise when the turn signal is operating. The sound no more signifies the presence of an actual electric relay than the kaKLICK-whirrr..rrRRRrrr..rrrriCK! sound a cell phone makes when it takes a picture signifies the presence of a folding mirror, focal plane shutter, and automatic winder for 35mm film. But people expect those sounds when you activate the machine, so the manufacturers provide an electronic noisemaker to make them.
Esmerelda, the Mustang (Esmerelda was beloved by Quasimodo, the Hunchback of Notre Dame, so calling her that tells you what I think of my physical beauty) is about as retro a car as has been made in the past ten years, but even she has the electronic noisemaker instead of the real thing. I found this out by practical experiment.
You see, Esperelda also has the nag chimes typical of all American cars (dagnappit). She bong bong bongs at me to fasten my seat belt. I believe in seat belts, but I don't wear one when I'm backing out of something, because it's too hard to turn around and look behind me with the seat belt on.
I'm also in the habit of having the turn signal that's on the car's outermost rear corner blinking away as I back out of a parking space. That way I have a flashing light out there, and if I didn't see some other car, maybe its driver will see me. An easy precaution to take, right?
Well, when I'm backing out of a parking space with my seat belt unbuckled and the turn signal going, Esmerelda is faced with a dilemma. She needs to tick-tock at me for the turn signal and Bong bong bong at me to nag me about the seat belt. But her noisemaker is single channel-- it can, apparently, only make one of those sounds at a time.
So she bongs at me for about ten seconds, as the turn signal flashes silently, and only then starts in with the turn signal noise. Busted!
So why do car manufacturers use such a piece of vacuum tube cleverness in modern cars? The answer is, at least usually they don't. Turn signals tick-tock because people expect that noise when the turn signal is operating. The sound no more signifies the presence of an actual electric relay than the kaKLICK-whirrr..rrRRRrrr..rrrriCK! sound a cell phone makes when it takes a picture signifies the presence of a folding mirror, focal plane shutter, and automatic winder for 35mm film. But people expect those sounds when you activate the machine, so the manufacturers provide an electronic noisemaker to make them.
Esmerelda, the Mustang (Esmerelda was beloved by Quasimodo, the Hunchback of Notre Dame, so calling her that tells you what I think of my physical beauty) is about as retro a car as has been made in the past ten years, but even she has the electronic noisemaker instead of the real thing. I found this out by practical experiment.
You see, Esperelda also has the nag chimes typical of all American cars (dagnappit). She bong bong bongs at me to fasten my seat belt. I believe in seat belts, but I don't wear one when I'm backing out of something, because it's too hard to turn around and look behind me with the seat belt on.
I'm also in the habit of having the turn signal that's on the car's outermost rear corner blinking away as I back out of a parking space. That way I have a flashing light out there, and if I didn't see some other car, maybe its driver will see me. An easy precaution to take, right?
Well, when I'm backing out of a parking space with my seat belt unbuckled and the turn signal going, Esmerelda is faced with a dilemma. She needs to tick-tock at me for the turn signal and Bong bong bong at me to nag me about the seat belt. But her noisemaker is single channel-- it can, apparently, only make one of those sounds at a time.
So she bongs at me for about ten seconds, as the turn signal flashes silently, and only then starts in with the turn signal noise. Busted!
