For a longer demo of the reader see this video:
For a description of the reader project see
Loading the Wumpus BASIC program from paper tape using my DIY paper tape reader. The tape is just an ASCII representation of the program and to the Altair appears to be coming from the keyboard input.
Altair BASIC requires at a break of least 200ms after receiving a carriage return character to process the newly entered line. The tape reader inserts these breaks automatically and therefore slows down when reading shorter lines and speed up for longer lines.