manual control must be continuously adjusted as the aircraft
changes altitude.
B.
Turn the range switch (S-1) from "OFF" to "SET".
This
connects the batteries and places the aircraft radiation
recorder in the circuit as a voltmeter indicating the B plus
voltage.
C.
Adjust the "B
0.70 ma. Since
of the recorder
which may cause
SET" control bringing the recorder reading to
this setting is critical, the paper in front
pen should be tapped, to overcome pen friction
erroneous readings.
D.
Start the recorder chart drive.
E.
Turn the range switch to a scale giving a convenient reading
on the airoraft radiation recorder or cantrol box meter.
An external voltmeter cirouit is
box meter (See Section 3.2.1)
required to drive the control
The ground-level radiation-intensity signal-voltage is a
combination of the aircraft radiation signal and the altitude compensation voltage.
Therefore it is possible to have a reading on scale
even when measuring a radiation intensity which is less than the
minimum value that can be measured on that particular scale.
Jf there
were no altitude compensation the recorder would read below scale, but
at high altitudes there might be sufficient altitude voltage
introduced to drive the recorder on scale.
As an example, this
condition would occur if the aircraft were flying at 500 ft. (fa-11.5)
and the radiation intensity at the aircraft was 0.05 mr/hr.
This
corresponds to a three foot intensity of 0.58 mr/hr and would be
indicated as such if the A scale is used.
However, if the B scale
is used the recorder will indicate 0.27 mr/hr (0.14 ma).
To prevent
this from occuring the operator should always check to make sure he
is on the lowest range scale (A,B,C, or D) giving an on scale
deflection on either the three foot level recorder or the meter on
the control box.
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