What's the difference between 33 1/3 60 vs 50 Hz?


This question comes from a previous post concerning a free strobe disk. At the site there is a 60 hz and a 50 hz version. I thought the hz is the # of AC cycle or at least is a measurement used for electrical purposes. The 33 1/3 is RPM's. Why are these measurements of 2 different entities used to make 2 different strobes. I understand why you need a different one for 45 or 33 but don't understand the difference that hz makes. Can someone explain this simply?
128x128artemus_5

Showing 1 response by albertporter

If you do not own a KAB strobe, you may substitute a neon test lamp used to check for hot electrical circuits. These look almost like a flat plastic ball point pen, but have two electrical leads.

Connect the leads permanently to an electrical cord, get the room dark and hold the test lamp next to the strobe disk. Electrical test lamps sold in the USA are all 60 HZ and very inexpensive. Possibly even available from Radio Shack.