i. Change the FREQUENCY RANGE to band 2 (1.7 to
5.5 GHz) and tune the FREQUENCY to about 2.0 GHz. Set
the FREQ SPAN/DIV to 100 MHz, switch the sweep gener
ator cw marker on and set it to 2.0 GHz. Adjust the
492/492P PEAKING control for maximum signal amplitude.
j. Return the sweep generator to its sweep mode and
set the Start/Stop markers for 1.5 and 2.5 GHz. Sweep the
1.7 to 2.5 GHz span for band 2 and note the frequency re
sponse. Frequency response or deviation must not exceed
±2.5 dB.
NOTE
If any segment or portion of the span fails to meet the
±2.5 dB specification, tune the 492/492P FREQUEN
CY to the center of this portion, apply a cw marker at
the center frequency and readjust the PEAKING for
maximum response. Decrease the FREQ SPAN/DIV
to display that portion and then recheck frequency
response.
k. Replace the 0.01 to 2.4 GHz sweep source with a 2 to
18 GHz sweep oscillator. Connect the test equipment as
shown in Fig. 3-7. On the RF plug-in, switch the ALC to Mtr
position and connect a coaxial cable between the Recorder
Output of the power meter and the Ext ALC Input of the
plug-in unit. Decrease the Power Level to approximately
— 6 dBm; then adjust the Gain for stable operation (output
stops oscillating).
I. Set the FREQ SPAN/DIV to 200 MHz and tune the
FREQUENCY to 4.0 GHz. Repeat the PEAKING procedure
with a 4.0 GHz marker and then sweep the upper portion of
band 2 checking frequency response. If necessary, recheck
those portions that do not meet specification after the
PEAKING control has been adjusted for that frequency
portion.
m. Increase the FREQUENCY RANGE to band 3 (3.0 to
7.1 GHz). Tune the center FREQUENCY to approximately
5.0 GHz. Apply a cw marker of 5.0 GHz, so the PEAKING
Calibration—492/492P Service Vol. 1 (SN B030000 & up)
Performance Check
Power Meter
To Recorder Out connector (Back Panel)
RG/58 BNC Cable
To Ext. ALC Input connector (Back Panel)
f
-ΐ':':: * ''vV: .-vy.' ..i: ..-
V
- * ·
• · · · ·
o · · ·
RF Unit φ
o
o
o
ft
©
To RF Out connector (Back Panel)
f
492 Spectrum Analyzer
N to SMA Adapter
3 dB Attenuator
Power Sensor
Power Divider
Low Loss Coax Cable with SMA Connectors
Fig. 3-7. Test equipment setup for measuring 2.0—18.0 GHz frequency response.
REV AUG 1981
3-19
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