some seriously cool obsolete technology
I came across this ad in my October 1943 issue of FLYING magazine and it caught my eye. It's a non-contact, optical tachometer that uses no electricity and doesn't need to have a special reflective tape added to the machine being measured.
Even cooler, it turns out that you can actually FIND them! I got this one in perfect mint, possibly unused condition in its velvet lined box with instruction booklet and 3 discs. The discs included with it measure speed ranges from 1000-4000, 4000-16000 and 8000-32000 RPM. There are ways to make it measure above and below these limits without any additional accessories, and it can also measure frequency of vibration as well as RPM .... which I guess makes it also a sort of mechanical oscilloscope.
This weekend a B-17 is coming to town, I plan to use this to read the RPM of its propellers.
some seriously cool obsolete technology
I came across this ad in my October 1943 issue of FLYING magazine and it caught my eye. It's a non-contact, optical tachometer that uses no electricity and doesn't need to have a special reflective tape added to the machine being measured.
Even cooler, it turns out that you can actually FIND them! I got this one in perfect mint, possibly unused condition in its velvet lined box with instruction booklet and 3 discs. The discs included with it measure speed ranges from 1000-4000, 4000-16000 and 8000-32000 RPM. There are ways to make it measure above and below these limits without any additional accessories, and it can also measure frequency of vibration as well as RPM .... which I guess makes it also a sort of mechanical oscilloscope.
This weekend a B-17 is coming to town, I plan to use this to read the RPM of its propellers.