|
|
|
|
|
|
Cartridge audio wire recorder
- this page is a stub
Textophon was an early wire recorder, 1
introduced around 1933 by
by C. Lorenz AG in Berlin-Tempelhof
(Germany). The device was used for recording audio onto a thin steel wire,
and to play it back afterwards. It was unique in that no open reels (or spools)
were used, as the wire spools were contained in a large metal cartridge,
or cassette, that could be swapped and resused easily.
|
Although it was a large device that was originally intended as a
dictation machine (dictaphone) or telephone answering machine,
it is listed here as a covert recorder,
mainly because it was
used by the German Federal Police during
World War II, for making covert recordings
of interrogations of prisoners of war, and arrested agents and spies.
The image on the right show the leftovers of a Textophon BE-4/III that
was rediscovered in 2015 in Germany. The device shown here was made in 1947
and is very similar to (but a bit smaller than) the earlier BW-4/II model of 1941.
|
|
|
The device is based on the Telegraphone [3], invented in 1898 by Valdemar Poulsen
in Denmark [1] and also on the Telephonograph, inventend in the same year
by the French engineer Jules Ernest Othon Kumberg [4].
It was used from 1933 onwards for telephone answering systems
and for central office dictation systems.
The machine was also adopted by the German Nazi party, and – in 1935 –
by the Reichs Rundfunk Gesellschaft (RRG) — the German Broadcasting
Corporation.
It is known from statements made by former engineer Semi J. Begun —
who worked for Lorenz in the 1930s before moving to America —
that the German Nazi government purchased thousands of Textophons
for tapping and recording telephone conversions of people under
surveillance [8].
In 1936, Textophon was the major recording device during the
controversal Olympic Games that were held in Berlin that year [5].
In many ways, the Textophon was based on a similar American device
– the Dailygraph –
of which the rights had been acquired by the American
ITT corporation.
ITT, who had become the major shareholder of Lorenz in 1930, passed
the device on to Lorenz for further development.
It is likely that the Dailygraph design was incorporated into Textophon.
|
 |
-
German: Stahltondrahtmaschine (steel sound wire machine),
Stahltondrahtgerät (steel sound wire device), or Stahltonmaschine
(steel sound machine).
|
- BW-1
First commercially available wire recorder from Lorenz, housed in a large
wooden enclosure that was usually placed on the floor. The top section
contained the wire cassette with the recording heads, whilst the lower part
contains the amplifier and the mains power supply unit. This version was developed
in 1933 and was delivered in large quantities to the German Nazi Government
in 1935 for telephone surveillance.
- BW-4/II
Improved design, housed in a wooden enclosure that is similar to that of the
BW-1 [6]. It would usually be placed on the floor and
requires a different – improved – design of the wire cartridge.
The initial design was made in February 1941, but the device was
probably not released commercially until 1942 [F].
- BW-4/III
Smaller variant, also housed in a wooden enclosure, that could be placed
on a table top. Based on the BW-4/II, but probably not taken into production
until relatively late in the war, probably 1945.
The machine featured on this page is a BW-4/III with serial number
47-038, that was manufactured just after the war in 1947.
|
The Textophon can be used as a stand-alone audio recorder — operated with
the controls at the front of the top surface — but also as a remote-controlled
unit, by adding the optional Steurstelle (controller) and the optional
Abhörstelle (play-back device). In such cases, the actual Textophon
was commonly placed in a centralized facility, depicted in the
diagram below as the control room.
In such cases, the controller is commonly placed on the desk of, say,
a company director, who dictates latters to the Textophon in the control room.
The controller is also suitable for the direct connection of a telephone
set, so that conversations can be recorded without a microphone.
A secretary can transcribe the recorded text directly from her own
desk, by using a small remote control unit known as the Abhörstelle
(play-back device), with a pair of headphones connected to it. The push-buttons
on the play-back device can be used to start, stop and rewind the wire.
|
|
|
German Police during WWII
|
|
|
During WWII, the German Police used the Textophon for covert
recording of interrogations of prisoners of war (POW) and – more importantly –
enemy spies and agents that had been caught while operating on German
territory. The diagram below shows a typical
setup as it was used by the German Police Department of Vienna (Austria),
recreated after the orignal WWII diagram [C].
In this setup, the microphone is hidden from view. Its signal is first amplified
in a sensitive pre-amplifier, after which it is amplified to line level by
an extra amplifier that also drives a relay, which means that it uses
voice actuated recording. The relay takes over the function
of the RECORD-button on the control unit, that is also hidden from view,
perhaps in the next room.
The signals from the control unit are fed to
the Textophon, which is located in the monitoring room, or in
a centralized facility elsewhere in the building.
An extra amplifier and loudspeaker are placed in the monitoring room, so
that people can observe the interrogation 'live'. Furthermore, a line feeds
the signals to the transcription desk (in the same room or in a separate office),
where a secretary can play-back the recording later, in order to produce a complete transcription.
|
Textophone was initially developed by Semi Joseph Begun, whilst
working as an engineer for the Ferdinand Schuchardt Fernsprech- und
Telegraphenwerk AG in Berlin (Germany), at the request of
the Echophon Maschinen AG
company – at the time owned by Kurt Bauer – who had acquired the manufacturing
rights for magnetic recording from Kurt Stille.
The major shareholder of Ferdinand Schuchardt AG, was Kurt Blattner,
who also made the Blattnerphones for the British BBC [9].
In May 1930, Begun's device was ready, and from June 1930 onwards, it
was sold by Echophon AG under the name Dailygraph. For the wire spools
he had used a cassette, or cartridge, based on
US Patent 1,665,784
of 1925 by Willy Hornauer [10]. The device was well known under the
name Dailygraph in the English-speaking world, in particular in the UK
and in the United States.
Around the same time (1930) the American
ITT corporation, acquired
the majority of shares of all three companies: Ferdinand Schuchardt AG,
Echophon Maschinen AG and C. Lorenz AG, and brought the development of
all magnetic recording activities under the umbrella of Lorenz.
The Dailygraph was renamed Textophon and was manufactured from 1933
onwards by C. Lorenz AG.
From 1934 onwards, the Textophon was further developed by Lorenz and in 1936,
the wire cartridge was changed for a version that was open on one side.
Textophon was initially marketed as a dictation machine, which had
the added ability to record directly from a telephone line. For this purpose,
it had been approved in 1936 by the German telecom authority Reichspost
[11].
|
|
|
Control unit
Steuerstelle
|
|
|
|
|
Play-back unit
Abhörstelle
|
|
|
|
|
Wire cartridge
Spulenträger
|
|
|
Conversation are recorded magnetically onto a steel wire that has a thckness
of just 0.22 mm.
The device is unique, in that it is one of the first devices on which the
wire was not supplied on open reels, but in a cartridge that could easily
be replaced by a non-expert. As far as we know, there were two designs of
this cartridge, that are very similar, bot not compatible with each other.
The first design was used with the
original Textophon BW-1. The improved version shown in the image on
the right was supplied with later models, like the BW-4/II and the BW-4/III.
|
|
|
Device Audio recorder Purpose Dictation, covert recordings, wire tapping Model Textophon Country Germany Manufactuer C. Lorenz Years 1933-1946 (est.) Medium Wire cassette Wire thickness 0.22 mm Recording speed unknown Wire length unknown Recording time 20 minutes (later: 30 minutes) Rewind speed 2 x recording speed Mains voltage 110, 120, 150, 220 or 240V AC, 50 Hz Rectifier valves Telefunken RGN-1064 (or Valvo G-1064) and Philips 328 Amplifier valves Telefunken REN-914 (or Valvo W-4110, or Philips E-499)
|
- Wikipedia, Wire recording
Retrieved January 2018.
- Wikipedia, Valdemar Poulsen
Retrieved January 2018.
- Wikipedia, Telegraphon
Retrieved January 2018 (German).
- Wikipedia, Telephonograph
Retrieved January 2018 (German).
- Wikipedia, 1936 Summer Olympics
Retrieved January 2018.
- Günter Hütter, Lorenz Textophon BW-4/II, S/N 8255
Personal correspondence, June 2017 — January 2018.
- Smithsonian Institute, Telephone Answering Machine
The National Museum of American History.
Retrieved January 2018.
- David Morton, Sound Recording: The Life Story of a Technology
ISBN 0-8018-8398-9, 2004-2007. Recording in World War II, p. 113.
- Museumsstiftung Post und Telekommunikation, Textophon mit Zubehor
Full title: Drahttonaufzeichnungsgerät 'Textophon' mit Zubehör.
Inv. nr: 4.2004.211.0. Retrieved January 2018.
- Willy Hornauer, US Patent 1,665,784
Electromagnetic Talking Machine.
Filed 20 June 1925. Published 10 April 1928.
- Reichspost, Ambtsblatt 1936 Nr. 51, Mitteilung 1216
Mitteilungen des RPM, 1216—1218. p. 219.
- Recording on a Steel Tape
The Wireless World, 29 June 1939. p. 611.
- H. Wildbolz, Das Textophon
Schweizer Archiv fur angewandte Wissenschaft und Technik (German),
Appendix Betrieb und Wirtschaft, No 10, 1943. pp. 9—12.
- Dr. Hans Joachim von Braunmühl, Magnetische Schallaufzeichnungen
Fortschritte und Spitzenleistungen.
Date unknown, but probably 1936. pp. 184—186.
- Von der Tonwalze zur Bildplatte
Audio (Magazine). Date unknown. pp. 43—44.
- Eduard Schüller, Das Magnetophon
pp. 428—431.
|
|
|
|
Any links shown in red are currently unavailable.
If you like the information on this website, why not make a donation?
© Crypto Museum. Created: Monday 08 January 2018. Last changed: Friday, 10 May 2024 - 06:02 CET.
|
|
|
|
|
