Philips PM 3347 Manual page 9

10
Controls and their functions
X-DEFLECTION
0
The X-deflection voltage is selected by means of the
3-position switch on the right-hand lower-side of the
unit.
Time base B
The X-deflection voltage is then supplied by time-
base generator B.
Adjustment of time-base B is effected in the same
way as described for time-base A, in the manual of
the basic oscilloscope.
The time co-efficient of time-base B can only be
adjusted in steps.
The length of the time-base can be adjusted by
means of the "LENGTH" control.
The time co-efficients are not influenced by this
control.
B Intensified by A
In this position also, the X-deflection voltage is sup-
plied by time-base generator B.
When switch "DEL'D TRIGG." is in position:
"STARTS A", the brightness-control voltage of time-
base Atogether with that of time-base B will be
applied to the Wehnelt cylinder of the CRT.
Consequently, the trace will be intensified during the
running of time-base A. By means of this indication,
that part of the trace can be selected, which must be
examined in detail.
When using the PM 3347 as a trigger-delay unit, the
trigger-mode switch of the basic oscilloscope may be
in any position but "AUT.".
A Delayed by B
In this position, time-base generator A supplies the
deflection voltage. Time-base A is started in the
same way as in position "B INTENSIFIED BY A".
This means that the part of the trace which was
intensified, is then displayed across the entire screen-
width.
ADJUSTING THE DELAY
If the PM 3347 is used as a trigger-delay unit, the
deflection switch should be set to position "B IN-
TENSIFIED BY A", to adjust the delay.
Time-base B is adjusted in the normal way by means
of the controls in the "TIME-BASE B" frame.
Fig. 2. X-Deflection
Fig. 3. Time-base B
Fig. 4a. B intensified by A
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Fig. 4b. A delayed by B
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Fig. S. Calculating the delay time