Have you ever wondered what the hash marks, black diamonds, and red squares on a tape measure mean? We'll help crack the code ...

The diamonds on your tape measure, sometimes known as joist marks, indicate the spacing between each joist center. The distance between each joist mark varies depending on the specific tape ...

They can be used to make a mark on the wood. The casing is also its own measuring tool. On the back, it will tell you how long it is so you don't have to curl the tape to measure a tight space.

If you want to try to figure out what’s going on for yourself, all you need is a pair of tape measures and a software defined radio (SDR), as [Tom Farnell] demonstrates. Tape measure antennas ...