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16. Check external triggering and trigger out
put operation
a.
et the Type 114 PERIOD control to 1 µ , s et the WIDTH
control to 100 n
and set the VARIABLE controls to CAL.
b. Connect a 50 Ω coax from the Type 180A MARKER
OUT connector to the Type 114 EXTERNAL TRIGGER — IN
PUT connector.
et the Type 180A for 1 microsecond markers.
c. Connect a 50 Ω coax from the Type 114 TRIGGER OUT
PUT connector to the Type 1A1 Chonnel 1 input (see Fig.
4-17).
et the Type 1A1 MODE switch to CH 1.
Type 1A1 Channel 1 VOLT /CM switch to 1.
d.
et the Type 547 TIME/CM IB] switch to 1 µ EC and
adjust the TRIGGER LEVEL control for a stable display. Check
for 1 pulse/cm of 3 volts amplitude ±1 volt.
e. Insert the 50 Ω termination between the coax and the
Type 1A1 Channel 1 input connector. Change the Channel
1 VOLT /CM switch to .2. The amplitude of the trigger pulse
from the Type 114 should now be between 0.4 and 0.7 volt
as measured on the crt.
f.
witch the Type 114 TRIGGER switch back and forth
between LEADING EDGE and TRAILING EDGE. The display
on the crt should flicker slightly and show minor differences
between the leading edge and trailing edge trigger pulses.
g. Turn the Type 114 PERIOD control to EXTERNAL TRIG
Fig. 4-17. Test setup for checking external triggerin g
GER and note that the display remains the same. Return the
PERIOD control to 1 µ
17. Check pulse risetime, falltime, and aber
the Type 1A1 VOLT /CM switch to 2.
OUTPUT connector and connect it to the OUTPUT connector.
Check to sec that the 50 Ω termination is between the 50 Ω
et the
coax and the Type 1A1 Channel 1 input connector.
Type 114 AMPLITUDE control for maximum positive output.
VARIABLE control for 5 cm of vertical deflection.
2 complete cycles in the 10 cm of the graticule (see Fig.
4-18).
4-18 do not exceed 5% peak-to-pe a k (2 ' / 2 mm or 1 '/ 4 minor
graticule division).
peat the aberration check.
Change the Type 547 TIME/CM (B) switch to .1 µ EC and
obtain a stable display.
Maintenance and Calibration — Type 114
rations
a.
et the Type 547 TIME/CM (B ) switch to .2 µ EC.
b. Remove the 50 Ω coax from the Type 1 1 4 TRIGGER
c. Obtain stable triggering and adjust the AMPLITUDE —
d. Rotate the Type 114 WIDTH — VARIABLE control for
e. Check that the aberrations, such as those shown in Fig.
f. Change the AMPLITUDE switch to — 3 to 10 V and re
g. Change the AMPLITUDE switch back to +3 to 10 V.
et
et the
4-11
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