The
Hellschreiber or
Feldhellschreiber (also
Hell-Schreiber named after its inventor Rudolf Hell) is a
facsimile-based
teleprinter invented by
Rudolf Hell. Compared to contemporary teleprinters that were based on
typewriter systems and were mechanically complex and expensive, the Hellschreiber was much simpler and more robust, with only two moving parts. It has the added advantage of being capable of providing intelligible communication even over very poor quality radio or cable links, where voice or other teledata would be unintelligible.