  Cherenkov detectors are in use today in small experiments as well as modern
ones as those at the LHC. This short note is about the construction of a small
Cherenkov detector with limited resources, which could be used to observe the
cosmic rays. The Cherenkov light obtained in this particular detector is read
with a photo multiplier tube and its signal is observed on an oscilloscope. The
detector construction can be achieved by relatively simple means and can be
used as an educational tool.
