Tektronix 1L10, Инструкция по эксплуатации

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Maintenance and Calibration— Type 1L10
adjusted for maximum distance from the base line. Also,
the display must have good symmetery. W hile making this
adjustment, keep in mind that the largest amplitude o f dis­
play is not the optimum point for the proper resolution.
In fact, proper resolution w ill occur when the display is
several db lower than the maximum amplitude settings of
L557, L537, C554 and C534.
1 cm wide at 3-dm down point
11.8 cm down) ^ 1
not to reach baseline.
Fig. 4 -1 5 . Location of Resolution adjustments and the desired wave­
form with the adjustments properly set. See Text.
3. Balanced Mixer Adjustment
a. Preset the front-panel
follows:
RF CENTER FREQ
RF CENTER FINE
FREQ
VERTICAL POSITION
R-F ATTEN
controls of the Type 1 LI 0 as
1.5 me
Midrange
Midrange
All OFF
GAIN
VERTICAL DISPLAY
DISPERSION-KC/CM
COUPLED RESOLUTION
INT OSC EXT OSC
Fully Clockwise
LIN
2
2
INT OSC
b. W ith no signal applied to the input of the Type
1L10, slowly turn the RF CENTER FREQ control from 1.5
me through 3 me and look for any signal indication on
the screen of the oscilloscope. Except for the possibility of
any stray external signal radiation, there should be no sig­
nals observed on the display produced by the Type 1 LI 0
(except for the inherent noise o f the system).
Fig. 4 -1 6 . Location of Balanced M ixer adjustments.
c. If any spurious signal is observed, position the signal
to the center o f the screen with the RF CENTER FREQ and
FINE RF CENTER FREQ controls.
d. Adjust C71 and C73 (Fig. 4-16) for minimum displayed
signal amplitude. After the adjustment is completed, maxi­
mum spurious signal amplitude is two times noise.
4 . Dispersion Adjustment
a. Connect the equipment shown in Fig. 4-17.
b. Preset the front-panel controls o f the Type 1 L I0 as
follows:
RF CENTER FREQ 10 me
FINE RF CENTER Midrange
FREQ
VERTICAL POSITION Midrange
R-F ATTEN All OFF
GAIN Midrange
VERTICAL DISPLAY LIN
DISPERSION-KC/CM 2
COUPLED RESOLUTION 2
INT OSC EXT OSC INT OSC
c. Set the output frequency of the r-f generator to 5 me.
d. Set the controls of the Harmonic Modulator Unit as
follows:
MOD 2 Switch O N
MOD 2 Knob Midrange
60-MC TRAP Switch IN
RF Knob Midrange
4 - 1 2