Tachometer FAQs:

Q: Were tachometers based on measuring the centrifugal force?

A: Yes, and similar to the operation of a centrifugal governor.

Q: Are tachometers used to estimate traffic speed and volume?

A: Yes, A vehicle is equipped with the sensor and conducts "tach runs" which record the traffic data.

Q: Is a tachometer often marked with a second scale in units of speed?

A: Yes.

Q: Are tachometers used extensively in rail vehicles?

A: Yes.

Q: Is a tachometer usually generated from an ECU which derives the information from either the crankshaft or camshaft speed sensor?

A: Yes.

Q: Are tachometers acceptable for high-fidelity sound playback?

A: Yes, but not for recording in synchronization with a movie camera.

Q: Is a tachometer a device that measures the speed of audiotape as it passes across the head?

A: Yes.

Q: Is a tachometer driven by the RMS voltage waves from the low tension side of the ignition coil?

A: Yes, while on others engine speed is determined by the frequency from the alternator tachometer output.