Section V Model 185B
Paragraphs 5-67 to 5-75
5-67. PERFORMANCE CHECK. g. Switch TIME SCALE to 10 pSEC/CM and adjust
DELAY as in step b.
5-68. TIME CALIBRATOR.
h Display should show 20 cycles in 10 cm *5 mm.
a. Connect equipment as shown in figure 5-5 and
set signal generator to 50 mc i250 kc.
i. Set Time Scale VERNIER to CAL and DELAY
to midrange and following table 5-8, check balance
b. Set channel selector on 187A/B to A & B.
of sweep time ranges for a IO-cm display *5 mm.
c. Adjust MODE, STABILITY and time scales and
vertical SENSITIVITY for convenient display. 5-73. MINIMUM DELAY.
5-74. Connect one vertical input to 50-MC CALIBFU-
d. Calibrator frequency must be within 1 mc of TOR output, set DELAY counterclockwise, and note
signal generator frequency.
that period of second cycle is equal-to period of last
cycle displayed.
5-69. SYNC PULSE.
a. Connect tee connector (187B-76E) and 50-ohm 5-75. TRIGGER SENSITIVITY.
termination (908A) to SYNC PULSE output.
a. Set TRIGGERING to NORMAL.
b. Connect one vertical probe to tee connector and (1) Connect signal generator (608D) to trigger in-
check: put and to vertical input probe as infigure 5-8.
Apply a 300-mv peak-to-peak, 100-mc signal.
Amplitude - at least 1-1/2 volts
Rise Time - 2 ns or less (2) Set TIME SCALE to 100 NSEC/CM.
Width - approximately 5 ps
(3) Trace should appear with proper adjustment
5-70. AMPLITUDE CALIBRATOR. of MODE and STABILITY controls.
5-71. Connect voltmeter (412A) to CALIBRATOR
output. Voltages measured on each range should be b. Set TRIGGERING to SENSITIVE.
within the tolerances listed in table 5-7.
(1) Repeat paragraph 5-75, step a, using 30-mv
peak-to-peak signal from generator.
I c. Set TRIGGERING to HIGH FREQ.
CALIBRATOR range 20 100 200 1000 MV
(1) Connect signal generator (612A) to trigger in-
Tolerance 0.6 3 6 30 mv put and to vertical input probe as infigure 5-5.
Apply a 150-mv peak-to-peak, 1000-mc signal.
(2) Steady display should appear with proper ad-
5-72. TIME SCALE. justments 'of MODE, STABILITY and HIGH
FREQUENCY STABILITY controls.
a. Connect one vertical probe to 50-MC CALIBRA-
TOR output.
Table 5-8. Time Scale Calibration Check
b. Set TIME SCALE MAGNIFIER to X100, TIME
SCALE to 2 pSEC/CM, and free run Model 185B and TIME SCALE MAGNIFIER Cycles/lO cm
adjust DELAY as far clockwise as possible and still
maintain 50-mc signal across full trace. 1 I.~SE~/CM X50 10
0.5 ~SEC/CM X50 5
c. Display should show 10 cycles in 10 cm *5 mm.
200 NSEC/CM x10 10
d. Adjust Time Scale VERNIER to make display
loo NSEC/CM x5 10
4 cycles in 10 cm.
50 NSEC/CM x5 5
e. Switch TIME SCALE to 5 pSEC/CM and adjust
DELAY as in step b. 20 NSEC/CM Xl 10
io NSEC/CM x1 5
f. Display should show 10 cycles in 10 cm &5 mm.
I
5-10 01255-1 |
ACEC
