Benutzer-Werkzeuge

Webseiten-Werkzeuge


en:hellschreiber_41

Hellschreiber 41

Hellschreiber 41 with the Hell printer T. empf. 14; manufactured by Siemens & Halske, Berlin.

The Hellschreiber or the teleprinter according to R. Hell was developed by Rudolf Hell in 1929; the Hell-Schreiber systems sold by Siemens were accepted with enthousiasm, especially in press and commercial radio.

The text messages in the form of a punched paper tape are converted by the Hell generator into a grid of 7 x 7 pixels and this signal is fed to the transmitter as a pulse sequence. In the radio receiver, the audio pulses are amplified and fed to a printer, which uses a writing spindle to print the message in duplicate on a paper tape.

Siemens Hellschreiber 41

Technical data

  • Principle]]: Teleprinter
  • Operation modes: Hell (quasi-facsimile system according to Dr Rudolf Hell)

Power supply

Dimensions

Accessories

System components

The Hell system consists of a „Hand punch“, into which the message is typed to create suitable punched paper tapes.
Siemens Hell: Hand punch


The various components are connected to the transmitter-side power connection box and can be switched on from a central power switch.
Mains power distribution box, transmitter side


The punched tape reader reads the punched tape and generates the Hell signal.

Siemens Hell: punched tape reader


An audio-frequency of 900 Hz from the Röhrensummer T. Sum. 5a (AF generator) is superimposed to the signal from the punched tape reader, the Hell signal is fed to the transmitter. Keying of the transmitter is done at the grid of the keying valve by on-off keying of the carrier wave.

Röhrensummer T Sum 5a


On the side of the receiving station, all the components are also plugged into a wooden power distribution box and can be switched on together.
Mains power distribution box


On the receiver side, the audio-frequency signal must be amplified (in the Amplifier T. Verst. 18a) and is fed to the Hell printer.
Amlifier T Verst 18 a


In the Hell Printer T. Empf. 14 a double screw is pulled by electromagnets to print the characters on the slowly moving paper strip.
Hell printer T Empf 14

If the speed is poorly synchronised, the two printouts of the message run at an angle, but the message itself remains legible. The synchronisation can be adjusted with the speed control until the two print strips run exactly parallel indicating optimum synchronisation.
Siemens Hell: Streifen

Technical principle

Character transmission in a quasi-facsimile process with 7 x 7 pixels.

Tube assembly

  • in the tube buzzer T. Sum. 5a: one EDD11, one fuse 300 mA
  • in the receiver amplifier T. Verst. 18a: one AF7, one AL4, one rectifier AZ1, one fuse 300 mA

Development

The sets developed by engineer Rudolph Hell were manufactured by Siemens & Halske, Berlin and sold for the civilian market.

Use

From the high power radio station G1.5K, the stations from serial number 15 onwards were equipped with the Hellschreiber 41, of which 13 systems were acquired. the system consists of two crates and the paper tape punch.

Technical documentation

Further information

en/hellschreiber_41.txt · Zuletzt geändert: 2024/01/14 19:40 von mb