TM 9-2320-211-20
(10) Falsifications and irregularities. C e r t a i n
recordings may seem impossible to explain from the
information given up to now. The cause may be an
u n i n t e n t i o n a l or intentional interference by the
driver or a defective instrument. The special design
o f the tachograph with its various mechanisms
o f f e r s a wide range of possibilities for checking
through which any irregularity can be ascertained.
In practice, falsification hardly ever occurs.
However, the following are descriptions of possible
falsification methods.
(11) Lowered speed.
( a ) Identifying feature. T h e s p e e d s t y l u s
records below the prescribed base line.
(b) Cause. The speed stylus is bent in order
to simulate lower speeds. To find the actual speed,
add the difference to the recorded speed. The in-
s t r u m e n t must be readjusted (fig. 2-293).
(13) Interrupted recordings.
(a) Identifying feature. A l l r e c o r d i n g s are
interrupted.
(b) Cause. The instrument cover has been
opened. If the distance recordings do not coincide
the vehicle has been used in the meantime. The
length of the journeys can be ascertained from the
difference between the recorded distance and the
distance counter figure shown in the inner field of
the chart (fig. 2-295). Also check whether the final
Figure 2-293. Lowered speed.
recorder figures coincide with the initial figures of
(12) No speed or distance recordings.
t h e next chart (fig. 2-296). If the values do not
(a) Identifying feature. T h e t i m e s t y l u s
coincide, trips have been made between removal of
one chart and insertion of the next one. Also note
records only traveling and stationary times; speed
the time of removal and insertion of the chart which
and distance recordings are not made.
is clearly marked. Normally a new chart should be
(b) Cause. The drive shaft is defective or
inserted at once. If the distances do coincide, the
has been intentionally unscrewed to conceal
chart may have been turned backwards to simulate
unauthorized trips. However, the driving of a trip
different working times.
c a n still be determined (fig. 2-294).
