DDR variant of the Hellschreiber
The Abtastfernschreiber or ATF (scanning teleprinter) was a field
developed between 1952 and 1954 by RFT in the former
East Germany (DDR) for the Kasernierte Volkspolizei (KVP) (Internal
People's Police). It was also used by the Nationale Volksarmee (NVA),
the People's Army of the DDR.
The machine was clearly based on the Hellschreiber system developed
by Rudolf Hell.
ATF is also known as FFS-002-00001, as RFT ATF Schreiber
and as Feldfernschreiber (FFS).
The original Hellschreiber
principle was patented by Rudolf Hell
and many Hellschreiber and Feldhellschreiber machines were used
by the German Army before and during WWII, both via landlines and over
short-wave (SW) radio links.
Hellschreiber machines were manufactured in a number of German factories,
including one in Berlin Dahlem that had opened in 1939 and another one
in Berlin Teltow that had opened in 1940.
Once the war was over, East-Germany
was separated from West-Germany and the factories ended up at the
Eastern Block side of the border.
Some of the Hell factories subsequently fell into East-German hands,
along with spare parts and the 'know-how'. So, when the newly
established People's Police (the Kasernierte Volkspolizei,
or KVP) needed a field teleprinter in 1952,
it was decided to use the acquired HELL-technology.
The image above shows the final version of the machine that was designated
FFS-002-00001. The letters 'FFS' are probably the abbreviation of
Feldfernschreiber (field teleprinter) and the number '002' tells us
that this was the second design. Globally speaking, the machine resembles
the original Feldhellschreiber.
It is housed in a sturdy transit case.
is located at the bottom
with a printer to its left.
The upper part
of the case contains the line amplifier
The basic design of th ATF Hellschreiber was created in 1952,
but the first machines were not deployed until 1954/1955,
when they entered service with the
KVP (Police) and later, in 1956, with the NVA (Army).
The FFS-002-00001 was part of Funkstation (radio station) FK 1a
and is described on pages 82-87 of the DV-44/14 operator's manual .
The machines were phased out in the late 1950s and the early 1960s,
at the height of the Cold War,
when new — more harmonized and interoperable —
systems were introduced to all countries of the Warsaw Pact.
The image below shows the ATF ready for use,
as seen from the front.
is at the bottom right, with a rather
small printer to its left.
The printer is capable of printing text as well as morse code (dots
and dashes). At the bottom left is a lever to select between
teleprinter operation and morse code. To the rear of the printer is a
small compartment for spare parts.
All connections to the outside world are at the
front panel of the
amplifier. From left to right are the sockets for connection of a field
telephone, a morse key, a transmitter and the (telephone) line.
At the far right are sockets for a pair of headphones
(monitoring) and a ground terminal.
A 125 Hz tuning-fork,
needed for speed adjustment of the motor,
is stored under the amplifier.
The machine is powered by a 12V DC source, such as the battery of a car,
which is connected to a socket at the left side.
Internally, the DC voltage is converted into AC by means of a vibrator unit
(German: Zerhacker). As these are sensitive devices, a spare vibrator
is present at the right of the cable storage compartment. The amplifier
to a socket behind the printer on the main unit by means of a
thick cable that is usually
stored in the cable storage compartment.
As it was strictly prohibited in the DDR to use former Wehrmacht nomenclature,
the new machine was called ATF, which is short for Abtastfernschreiber
(scanning teleprinter). The first version of the ATF appeared in 1952 and
was built by the RFT consortium
. To this day it is unclear which member
of the RFT group
was responsible for the manufacture and/or which former
HELL plants were used to source the components and knowledge from,
but it was likely to be based in Berlin.
The image above shows the initial version of the ATF Schreiber  as it was
built by the RFT consortium
in Berlin. It is the predecessor of the FFS-002.
It is believed to be the only surviving sample of this machine and is part
of the collection of the Military Historical Museum in Dresden.
RFT ATF Schreiber ATF-00001
The development of the RFT ATF Schreiber eventually led to a redesign
of the final machine — the FFS-002-00001 —
which went into production
in 1954/1955, most likely in a factory in or near Berlin, as
this is where the know-how and the parts from the wartime HELL production
were located. It is currently unknown how many FFS machines were manufactured,
but by studying the serial numbers of the surviving machines, it is
possible to make an educated guess. Bernd Rothe estimates in his
description of the FFS  that around 400 machines were produced,
divided over two production runs. The following serial numbers are known:
- 12320 ← our machine
The 4-digit numbers (starting with '80') are probably from a pre-production
prototype run, the so-called XATF-Schreiber. These machines were later
converted to KVP/NVA Feldfernschreiber machines. In total, the existence
of 11 machines could be confirmed , 5 of which were more or less
complete. The rest were just fragments that could only be used for
spare parts. Of the remaining five machines, only
two have been fully restored, one of which is part of our collection.
The other one is in the collection of the Communications Museum (MFK) 1
in Frankfurt (Germany).
MFK = Museum für Kommunikation (Communications Museum).
Although the ATF uses the same printing principle as the original
Feldhellschreiber, the actual printer itself is constructed quite
differently. First of all it is a lot smaller and it is driven by
the main motor which is housed in the lower part of the machine,
whilst the motor of the original Feldhellschreiber was placed
vertically above the printer.
The image on the right shows the printer
and paper path that are
normally covered by a small hinged lid at the front left of the
machine. A plastic window in the top lid
allows the printing
mechanism to be inspected without opening it.
A narrow paper strip is fed in from the paper compartment
at the right, along a black metal strip. At the bottom is the
ink roller which deposits its ink, via a small black roller,
onto the square print head. The print head is pressed against the
paper in the rhythm of the 900 Hz tone signal from the telephone
line or radio.
The major difference with the original Hellschreiber is the
construction of the printhead. The print head of the ATF has
four slightly curved sides, with a diagonally embossed
line on each of the side surfaces, whereas the print head of
the Feldhellschreiber is cylindrical with two embossed
spirals on it. The effect is the same however, and results in
two lines of text being printed.
The printer is driven by the main motor which is located in the
bottom section of the machine. A collector's-find in Germany
in 2008  tells us that initially motors were used from the
wartime production of the Rudolf Hell factory in Berlin-Dahlem.
The motors were later reproduced by VEB Elektromotorenwerk
Hartha (a.k.a. ELMO).
The motor speed of 3750 rpm is stabilized by a centrifugal switch
that can be adjusted with a small screw at the
front of the printer,
with the aid of a 125 Hz tuning-fork in
combination with the stroboscopic disc
at the front of the printer.
ATF Hellschreibers are extremely rare and therefore highly wanted
collectors items. As far as we know, there are only
six surviving examples
of the FFS-002 and just one of the early RFT-ATF teleprinter.
The latter is in the collection of Military Historical Museum in Dresden
The FFS-002 featured on this page, was found on Ebay in May 2009.
Although the machine looked allright in the photographs on Ebay, it
appeared to be in bad non-working condition.
Luckily, our friend Bernd Rothe from Dessau came to the rescue.
First of all he collected the machine from a small town near the Polish
border, a return trip of 900 km. The machine was badly damaged by water,
probably from storage in an old shed, and some critical parts were missing,
but Bernd was determined to restore the machine and get it going again.
As the owner of the only working FFS-002 at the time, Bernd had sufficient
spare parts to restore the machine and when we came to collect it a few days
later, the driving mechanism was already running again. The image above
shows Bernd at work in the small garage near his home in Dessau (Germany).
And after another day of hard labour, the machine printed its first message.
One of the major difficulties was the driving motor. After years of
storage, the main shaft had become blocked and was beyond repair.
Luckily, an original refurbished HELL-branded motor
was available as a drop-in replacement.
Another problem was the vibrator unit that is needed
to convert the DC voltage into AC. After years of storage
they become oxidised and are often beyond repair. For this reason a spare
unit was normally supplied with the ATF. Although it can be
replaced by a modern electronic variant, Bernd managed to repair
the original vibrator.
We are most grateful to Bernd Rothe for his time, help and expertise
when acquiring this ATF Schreiber and bringing it back to life again.
For the restoration he used original parts from ATF fragments
that he had found over time.
Sadly, Bernd passed away unexpectedly on 1 December 2013 at the age of 66.
He will be missed dearly.
His ATF Schreiber is now part of the collection of the
Museum für Kommunication (Communications Museum) in Frankfurt (Germany).
- Principle: ATF-HELL
- Modulation: A2 ATF-HELL, A2 Morse Code (CW)
- Tone frequency: 900 Hz (single tone)
- Transmission: asynchronous (start/stop)
- Transmission speed: 225 baud
- Typing speed: 4 cps (characters per second)
- Period: 250 ms
- Raster: 56.5 fields with 7 lines each
- Single line: 7 pixels
- Information: 155.5 ms (35 fields of 7 lines each)
- Start + stop: 94.5 ms
- Pixel: 4.44 ms
- Power: 12V DC
Document obtained from Bundesarchiv Freiburg and kindly provided by Frank Doerenberg .
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© Crypto Museum. Created: Wednesday 29 June 2016. Last changed: Thursday, 07 November 2019 - 14:20 CET.