TB 9-6625-2134-24
(2) VERTICAL DISPLAY 10 dB/DIV pushbutton on.
(3) FREQUENCY SPAN/DIV control for 100 kHz.
(4) AUTO RESOLUTION pushbutton on.
(5) DIGITAL STORAGE PEAK/AVERAGE control fully cw.
8. Frequency Accuracy
a. Performance Check
NOTE
Throughout the procedure, when an out-of-tolerance condition
is noted, perform the adjustments listed in 8 b below before
continuing with the calibration.
NOTE
Due to residual magnetism buildup in the 1st (YIG) oscillator
tuning coils, accuracy of frequency readout should be checked
after tuning coil has been degaussed by pressing DEGAUSS
pushbutton. Degauss when FREQ SPAN/DIV is either
2 MHz or 1 MHz before reducing FREQUENCY SPAN/DIV
control to 500 kHz.
(1) Connect microwave comb generator to RF INPUT 50Ω.
(2) Position TI controls as listed in (a) through (d) below:
(a) FREQ SPAN/DIV control to 200 MHz.
(b) FREQUENCY control to 1.0 GHz.
(c) MIN RF ATTEN dB control to 20 dB.
(d) VIDEO FILTER WIDE pushbutton to on.
(3) Position 1.0 GHz microwave comb generator signal to center of crt while
decreasing FREQ SPAN/DIV control to 1 MHz.
(4) Press DEGAUSS pushbutton and position FREQUENCY SPAN/DIV control to
500 kHz.
(5) Center 1.0 GHz microwave comb generator signal with frequency dot on crt by
adjusting FREQUENCY control.
(6) Press IDENTIFY 500 kHz ONLY pushbutton to on and verify signal is a true
response.
NOTE
When IDENTIFY 500 kHz ONLY pushbutton is on, vertical
position of display alternately shifts about one division.
(7) Upon verification, press IDENTIFY 500 kHz ONLY pushbutton to off.