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Last page update: 3 February 2017


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INTRODUCTION

A 1941 Siemens-Halske patent (ref. 1) proposes a flexible "building block" ("Baukasten") Hellschreiber system. The concept comprises several modules (see Figure 1):

  • Hell-printer with motor
  • vertically oriented paper-tape cassette
  • keyboard-sender with built-in paper tape cassette-drawer
  • punch-tape sender with built-in paper tape cassette-drawer

Presse hell peripherals

Fig. 1: the modular Siemens-Hell concept

(source: adapted from ref. 1)

The printer module includes the motor, so this module is always required. With it, the following three configurations can be made, by attaching one of the other modules:

  • stand-alone "printer only" (item 1 in Fig. 2), as a possible replacement for the "Presse-Hell" printers.
  • "printer + punch tape sender" (item 2 in Fig. 2)
  • desktop "printer + keyboard sender" (item 3 in Fig. 2)
Presse hell peripherals

Fig. 2: three modular configurations

(source: adapted from ref. 1)

The printer-motor module has two output gears. The one on the right can drive a keyboard-sender or punch-tape-sender unit. The one on the left is for driving a callsign-generator module ("Namengeber", to transmit the station identifier). The latter is not detailed further in the patent. Note that such a callsign-generator is not particularly complicated. The photo below shows the optional Hellschreiber-style motorized 6-character callsign-generator of the 1947 ETK47 teleprinter from the Swiss company GRETAG.

GRETAG

Close-up of the optional ETK47 callsign generator - similar to the notched character drum of Hellschreiber senders



THE PRINTER-PUNCH-TAPE-SENDER "T.SEND.46"

To date (2017), only the development and production of two of the four modules can be confirmed: the motorized printer module and the punch-tape-sender module.

Presse hell peripherals

Fig. 4: the "printer punch-tape-sender" configuration

(source: adapted from ref. 1)

Combined, they form the Siemens-Hell "Geber-Empfänger" ( = sender/printer). Compare the photo below to Fig. 4 above:

Presse hell peripherals

Fig. 5: SH-Geber-Empfänger


Presse hell peripherals

Fig. 6: SH-Geber-Empfänger - restored by P. Trepte

(original unedited photo: © P. Trepte; used with permission)

The label on the punch-tape reader module only identifies it as an "SH GEBER-EMPF." I.e., a Siemens-Hell "Geber-Empfänger" ( = sender/printer):

Presse hell peripherals

Fig. 7: label on a 1946 "SH Geber-Empfänger"

(source: courtesy P. Trepte)

The label design is identical to that of the Hell Feldfernschreiber, as is the drab color - it probably came from WW2 stock. There is no model number or designator marked on the label or elsewhere on the outside of the unit. However, T send 46 is marked inside the punch-tape-sender unit, on the casting of the chassis:

Presse hell peripherals

Fig. 8: "T send 46" boss on the cast chassis

(source: courtesy P. Trepte)

Per the label, this unit was built in 1946. The "46" in the type designator "T send 46" may correspond to this, as the year of entry into service of this model. It has a standard "Presse Hell" printer module, with a small DC-motor behind it. The motor has a centrifugal speed regulator, similar to that of the Feld-Hell - but without an overspeed protection contact. A drawer for the roll of the printer's paper tape is located below the sender.

Presse hell peripherals

Fig. 9: SH-Geber-Empfänger "T.send.46" - cover removed


Presse hell peripherals

Fig. 10: top view of the "T.send.46" - selector bars and contacts of the character-drum clearly visible

(note the double gearing behind the motor on the far left)

The actual printer mechanism is the standard, unchanged "Presse Hell" model with the felt ink-roller on the lever above it:


Presse hell peripherals

Fig. 11: the Presse-Hell printer module has its own motor with centrifugal speed regulator


On the front of the punch tape reader, note the start/stop buttons for sending the special E-shaped Feld-Hell pause-character:

Presse hell peripherals

Fig. 12: start/stop buttons for the E-shaped Feld-Hell pause-character



The German post-war news agency DANA initially operated under the direction of US Brigadier General Robert A. McClure. On 26 October 1946, DANA was officially handed over to an association of German newspaper publishers. A 1946 printer-punch-tape-sender was operational at the licensing ceremony:

Presse hell peripherals

Fig. 13: October 26, 1946 - licensing ceremony of DANA - with a T.send.46 on the desk

(source: ref. 3, courtesy P. Trepte)

The Swiss army acquired at least one of these machines, and gave it the station designator "St. aps. 31 a":

Presse hell peripherals

Fig. 14: S-H printer-punch-tape-sender of the Swiss Army

(©2016 M. Boesch; used with permission)

There is a light-gray knurled wheel that partially sticks out of the top left of the printer-sender machine (behind the vertical lever of the printer module). This is the adjustment knob for the motor speed. Per the label, the unit is powered by 220 VAC.

Note that the printer-sender unit has an additional module that is attached to the left of the printer module. Its function is still to be determined. Possibly, it is the callsign-generator that is mentioned in the patent. On top of it, there is a small switch box, to toggle between sending and receiving via telephone wires. It has binding posts on the back, for wires and banana plugs.

Also note the black button with green dot at the center of the photo (also visible in Fig. 4, 5, 8, and 10, but not in the patent drawings). This is the "Morse" telegraphy key that is taken directly from the Feld-Hell keyboard.


This machine does not contain the electronics that are required to 1) key the electro-magnet of the printer module on and off in the rhythm of received Hell tone pulses, and 2) to generate the tone signal that is keyed on and off by the punch-tape sender. The electronic circuitry would comprise several radio tubes (valves) that would have to be supplied with an anode voltage. The motor does not drive an anode voltage generator, so that voltage would somehow have to be derived from a DC battery or AC mains voltage. The patent foresees an electronics module with built-in power supply. It would by attached to the right hand side of the keyboard-sender or punch-tape-sender. Again, there is no evidence that such a module was ever developed.

The Swiss Army's machine was used with a standard Siemens-Halske printer keying amplifier model St.V.1b, a tone generator model St.sum.1a, and a custom power supply in a wooden box (selectable 110/135/165/220/250 VAC in, 2 x fused 220 VAC out):

Presse hell peripherals

Fig. 15: peripherals used with the Swiss Army's machine

(original unedited photos: ©2016 M. Boesch; used with permission)


The 1941 patent mentions one more configuration, combining three modules into a carrying case: the "printer + motor" module, the "keyboard-sender + paper tape cassette" module, and an electronics module ( = amplifier, tone-generator, power-supply). I.e., the next generation Siemens-Hell Feldfernschreiber. The patent actually references the existing Feld-Hellschreiber several times.


REFERENCES


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©2004-2016 F. Dörenberg, unless stated otherwise. All rights reserved worldwide. No part of this publication may be used without permission from the author.