The high speed telegraphy transmitting system "MFA" has been developed by the precision mechanics company Moser-Baer, Sumiswald. It consists of a keyboard perforatorr Sl b, the transmitting unit GS 200b, the printing unit SR 200b and and electro - mechanical paper tape transport unit.

The keyboard perforator SL b, which comes in it's own crate (37,0 kg with accessories) and can be powered from 125 - 250 Volts AC, a punched paper tape with the text message is generated.
The motor runs with constant speed, the transport head moves the paper tape at constant speed and the punching head punches the transport holes and the holes for the morse code characters.
On the paper tape, there are transport holes in the middle, these are generated, when the space key for a space between two words is depressed. Two holes on both sides of the transport hole in the middle code for a dot (Punkt) and two diagonal holes code for a dash (Strich) in morse code.