Tell is the tradename for scopes of a company named Kaufmann.

They were build in Wetzlar where many companies like Hensoldt produced scopes and other optical devices.
Difficult to name the maker of that special scope.

Tell scopes should not be mingled with the arms maker Tell ( Venus-Waffenwerke , Zella-Mehlis).

The name "Tell" has its origin in the Swiss freedomfighter Wilhelm Tell a renowned crossbow shooter, standing for precise shooting capability.