This old tachometer uses music box type reeds to measure motor RPM without electricity. It's more useful than a digital Tach because it shows you resonant frequencies and can be used to check hammer and reciprocal speeds too. Thanks for helping me make more movies, I appreciate your help. Early access here: http://www.Patreon.com/AvE
Friggin cool
I've used a spring tachometer on small engines before that works on the same principle.
It was a coil of spring steel wire in a housing that you placed on top of the engine and extended the wire to its maximum point of oscillation and read the corresponding number in the housing section.
Not nearly as accurate, I'm sure simply because of the human factor in proper application..
This is brilliant… Simply brilliant
I wonder if you could use it to tune a musical instrument
I love 20 minutes from Plymouth Meeting PA. So cool!
I think that they used to use those for adjusting the RPM's on small engines also. A very brilliant idea. This goes to show the genus of Nikola Tesla, who in my mind is the father of anything to do with frequency, sound and vibration. And also electricity, if he had been successful and had his way there would be no power cables or phone wires cluttering up the skys EVERYTHING would have been wireless.
That's just lovely.
I just looked and Cole-Parmer still makes those !!!!
Accordion repairman here: it’s not easy to make reeds. I would know.
Genius resonance frequency use? Love this kinda stuff
Still made by stitchco. Still extremely expensive
Seen these on old POS harbor tugboats. Electrical panel had these to show diesel genset rpm, along with the old-school triple light bulbs, for synchronizing the generators in parallel. Looks janky compared to new systems, but always worked.
It looks like a harmonica
B e a utiful