Tektronix 1L10, Инструкция по эксплуатации

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Maintenance and Calibration— Type 1 LI 0
Fig. 4 -1 8 . DISPERSION CAL (R 321) adjustment.
e. Set the output frequency of the audio generator to
8 kc.
f. Set the RF CENTER FREQ control of the Type 1L10
to bring the second harmonic of the 5 me signal onto the
screen. Use the FINE RF CENTER FREQ control to posi­
tion the 5 me signal to the centerline of the graticule.
Momentarily turn off the M OD 2 switch on the Harmonic
Modulator Unit to establish that the center-frequency marker
is on the centerline of the graticule rather than one of
the 8 kc sidebands.
g. Set the DISPERSION CAL R321, (Fig. 4-18) adjustment
for exactly four graticule divisions between the center-fre­
quency marker and the sideband marker on the right-hand
side of the graticule.
h. Adjust L374 for exactly four graticule divisions between
the center-frequency marker and the sideband marker on
the left-hand side of the graticule.
i. Steps g and h interact. Repeat these steps until no
further adjustment is necessary.
j. Check the dispersion at all settings of the DISPERSION-
KC/CM as per the "Dispersion Check" in the Checkout
Procedure.
5. Oscillator Tracking Adjustment
a. Set up the equipment as shown in Fig. 4-19.
b. Set the front-panel controls as follows:
RF CENTER FREQ
RF CENTER FINE
FREQ
VERTICAL POSITION
R-F ATTEN
EXT OSC INT OSC
VERTICAL DISPLAY
G A IN
DISPERSION-KC/CM
COUPLED RESOLUTION
36
Midrange
Midrange
All OFF except 16db
and 20 db
INT OSC
LIN
Midrange
2
2
5 mSEC/CM
Oscilloscope Sweep Rate
Leave the Oscilloscope power OFF
4 -1 3