Minifon P55 "Plexi". Portable lamp wire recorder. Made in Germany by "Protona
GmbH"; Hamburg. P55 recorders manufactured from 1955 to
1960, but this unit is the first series in the plastic
case was made not later than 1957. That's what this says
Roland Shellin in soybean book "Minifon Spy in the pocket"
(Roland Schellin, "Minifon Der spion in der tasche"), in which
he talks about the history of all models Minifon.
Translation: The original
machines were still P55 plastic case.
Translation: The original design
of the whole was placed in a plastic case.
Therefore, devices in this series was often
called procto "Plexi". Starting around 1957
plastic housing was replaced by cast-art
Dimensions recorder 177 x 102 x 40 mm.
Weight 600 g without batteries. As the magnetic carrier
used wire from a special magnetic alloy with a diameter
0,05 mm or 0,038 mm. Circuit collected on three
subminiature vacuum tube (See wiring diagram at the bottom
of the page), in connection with which to supply the required three
different voltages. Engine 6 - 12 v, the anode voltage -
30 v, filament voltage - 1,5 v. The engine has
electromechanical stabilization speed. On the shaft of
the engine is a centrifugal regulator. Electric
stabilizer consists of several parts, one of which - a
diode protection for the engine. Active element of the
stabilizer is a miniature incandescent lamp. During the
unit head moves up - down uniformly laying wire on the
coil. In combination with good stabilization of the
rotational speed of the engine, it allows to minimize
the distortion of records associated with the unstable
speed wire. There hitchhiking. When the coil wire ends,
she pressed the lever is released. This lever, in turn,
presses the power circuit breaker, located under the
coil. When firing hitch red signal lamp lights. It is knownthat the modelP55in 1955sold for$289.50. Structurally Minifon P55 "Plexi" is very different from
later models P55. In the "Plexi" top cover contains no
loops, it just slipped from the top and latch, and jack
of the external power launched into the side wall of the
housing. Internal structure also has significant
differences. In particular, the "Plexi" bearing spindle
table built directly into a plastic deck. All the
differences can be seen by comparing the "Plexi" with
more recent models in the pages of Minifon P55 L (1957)
è Minifon P55
L (1960). There you can read the other information on
Externally, the unit survived very well. Inside and
everything was in place, not counting the fact that old
age is completely destroyed and the rubber roller Belts
fast. I already have a serviceable recorders
Minifon P55 later
versions, and this device, I initially decided not to
rebuild. However, later on, making sure that repairs do
not require major intervention in the original design, I
decided to have it repaired. After lubrication mechanics,
replacing rubber belt and rubber roller rewind machine
is functioning well.
Photos can be enlarged
In the photo at the bottom of the speed
selector. Left switch in the increased speed for
recording music, and the right-lapse recording speech.
As an accessory to recorders made Minifon
desktop speakers with an amplifier, combining the
functions as a microphone and transmitter for
non-contact recording from the telephone. For more
details about their designs on the pages can be
Rubber belt of old crumbled into dust,
and was completely damaged tires on the roller rewind
Photographs taken during the repair.
The original batteries 12 v engine for
A set of original batteries for recorders
On the left the original mercury battery
1,4 v types Mallory Duracell ZM-9 (AA). In the photo on
the right the original battery type 30 v Mallory RM-413,
its modern equivalent Eveready 413, and a homemade
battery 30 v, collected from three batteries MN (12 v +
12 v + 6 v).
Power supply 12 v to type recorders
Specification and wiring
diagram Minifon P55. Photos from the book by
Roland Shellin "Minifon Spy in your
Schellin, "Minifon Der spion in der
tasche"). In recorder Minifon P55
"Plexi" instead of radio tube XFY54 it is used XFY43.