The HC-570 is a desktop cipher machine developed by
Hagelin in Switzerland in the late 1970s.
It is part of the CRYPTOMATIC family of machines and is
compatible with the HC-520 pocket device
and the HC-530 suitcase cipher machine.
It was amoung the first fully electronic cipher machines that were developed
as the successors to the ageing H-4605.
The image on the right shows a typical Hagelin HC-570. The machine is rather
large, even for a desktop machine, and its bottom is an integral part of the
carrying case. The hood, that has been removed in the image, carries the
supplies and accessories, such as the manual, instruction card, cables
and paper tape.
All input is via the alphanumerical keyboard at the front of the unit,
or the paper tape reader (front right).
Output is via a display, just above the keyboard, the built-in printer,
the paper tape puncher (right) or directly to the line (rear).
The unit is operated via two key-locks to the left of the power switch.
The rightmost one (secundary key) is used to enable ciphering and deciphering.
The leftmost key is the primary one. It is used for opening the case and for
entering the Basic cryptographic Key (BK).
The HC-570 has a wide-range power, suitable
for all mains voltages between 90 and 250 V AC.
The HC-570 needs two physical keys
for its operation. They are both located to the left of the power
switch and are of the rather complex KESO type.
When we first acquired this machine in December 2010, we were unable to
open it, as the primary KESO key was missing. This key was needed to operate
the locks that keep the top lid closed, as well as to
set the Basic Key (BK).
Luckily, key expert Barry Wels [3], was willing to help us out.
Barry helped us before in 2009, with the creation of a new key for our
Enigma M4
without removing or forcing the lock.
On 25 March 2011, Barry visited us again and produced a
working key from scratch, using a technique called impressioning.
The image on the right shows the resulting key. It looks in no way like a
genuine KESO key,
but operates nevertheless smoothly.
Unlike an original KESO key, the impressioned key is not symmetrical
and can only be inserted one way around.
Starting off with a blank polished key, Barry wiggles it inside the lock.
He then searches the key for minor scratches and files away the unwanted
parts. This process is repeated numerous times, until the lock finally
gives in. Although it sounds easy, it is in fact a tedious job which
requires a skilled expert. Check the video below to see the final stages
of impressioning the key.
below. Click any of the thumbnails
to enlarge. If you want to learn more about lockpicking and creating keys
from scratch, you might want to check out Barry's website.
We will soon post new details about the Hagelin HC-570.
Interior
Now that we have the primary key for this machine, we are able to remove
the cover and examine the interior. Apparently, our HC-570 is complete and,
apart from a minor issue with the printer transport mechanism, in very good
condition.
The image on the right shows the machine after removing the cover.
Right behind the display is the thermal printer, which appears to be a
stand-alone unit. To the right of the printer is the paper tape puncher
with a semi-transparent chad box at the right.
At the rear left is the power supply unit (PSU). To the right of the PSU
are 15 electronic PCBs, mounted together in a frame. All components are
of the highest standard and the PCBs are all coated in order to protect the
components against moist.
At the front right is a small paper tape reader. It is a stand-alone unit
that is mounted in such a way, that it protrudes a hole in the top cover.
This way it can be accessed from the keyboard. More detailed images of the
interor below.
