Tektronix 1L10, Инструкция по эксплуатации

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Maintenance and Calibration— Type 1L10
the accuracies given in Section 1 o f this manual.
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TROUBLESHOOTING
Equipment Required
1. Tektronix oscilloscope that is normally used with the
Type 1 LI 0 Spectrum Analyzer.
2. Tektronix Type 180A Time-Mark Generator.
3. Tektronix Type 105 Square-Wave Generator.
4. Calibrated-Frequency Audio Generator capable of sup­
plying 10-cycle to 2-kc signals with a frequency accuracy
o f ± 1 % . The output amplitude shall be variable 0-1 volt
rms.
5. Calibrated amplitude source of r-f power at frequencies
between 1 me and 60 me. Output amplitude of the generator
should be variable from Odbm to — 100 dbm ± 1 % (0 dbm
= 1 milliwatt). The frequency generator and attenuator
must be well shielded to prevent stray radiation.
6. Tektronix Harmonic M odulator Unit, Tektronix part
number 067-0518-00.
General Information
If trouble develops in the Spectrum Analyzer, first check
for proper connections and control settings. Look for simple
explanations for the trouble first, before getting involved in
detailed troubleshooting.
If all connections and control settings are proper, make
a visual check o f the instrument. Check and correct any­
thing observed that could cause trouble.
Also, check the oscilloscope to make sure that it is operat­
ing properly. A faulty power supply in the oscilloscope can
cause a variety o f unusual trouble symptoms. The quickest
way to check the operation of the oscilloscope is with an­
other plug-in unit if one is available. If faulty operation is
still noted with a different plug-in unit, the trouble can be
assumed to be in the oscilloscope.
The Checkout and Calibration Procedures in this section
are helpful in isolating trouble to a particular circuit.
7. Connecting cables, 50-ohm with BNC connectors, 4 each
Tektronix part number 012-0057-00.
Preliminary Setup
The following steps apply throughout the Checkout Proce­
dure except as noted.
1. Insert the Type 1 LI0 Spectrum Analyzer into the oscillo­
scope, turn on the power and allow about 20 minutes for
warm up.
2. Connect a patch cord between the SWEEP INPUT con­
nector o f the Type 1 LI 0 and the Sawtooth output connector
o f the oscilloscope.
3. Set oscilloscope time-base for a free-running sweep.
Sensitivity Check
1. Set the front-panel controls of the Type 1L10 as follows:
Signal tracing is another important method o f trouble­
shooting. Voltages and waveforms are shown on the sche­
matic at points that facilitate signal tracing.
CHECKOUT PROCEDURE
Preliminary Information
This procedure offers a systematic way of checking the
Type 1L10 against the requirements of Section 1 of this
manual. The Checkout Procedure should be performed
routinely after each 500 hours of operation or every six
months if the instrument is used intermittently. Also use the
Checkout Procedure after any corrective maintenance work.
RF CENTER FREQ
FINE RF CENTER FREQ
VERTICAL POSITION
R-F ATTEN
EXT OSC INT OSC
VERTICAL DISPLAY
G A IN
DISPERSION-KC/CM
COUPLED RESOLUTION
10
Midrange
Midrange
All OFF
INT OSC
LIN
Fully clockwise
2
2
2. A pply the output signal of the calibrated amplitude
r-f generator to the RF INPUT 50 0 connector of the Type
1 LI 0 (see Fig. 4-2). Set the output of the generator for about
—50 dbm.
Aways perform this procedure before attempting to cali­
brate the instrument. This w ill avoid making unnecessary
calibration adjustments in many cases.
3. Vary the frequency of the r-f generator and the RF
CENTER FREQ control of the Type 1L10, if necessary, to
bring the signal onto the screen.
The test equipment required for this precedure must meet
or exceed the accuracies specified under “ Equipment Re­
quired". If the equipment used does not meet these require­
ments, the Type 1 L I0 cannot be checked or calibrated to
4. Decrease the output amplitude of the r-f generator
to — 100 dbm and note the relative amplitude between the
displayed signal and the noise displayed on the trace (see
Fig. 4-3). The signal must be twice or more the amplitude of
4 -2