Motorola R-20018 Manual page 49

Communications system analyzer
Table of Contents

Advertisement

5-136.
Frequency Counter
1.
Set the UUT to the Gen CW Mode with an output frequency of 35 MHz at a level of 0 dBm as displayed
on the Gen/Mon Mtr display. Connect the RF In/Out Jack to the Counter In Jack of the UUT. Select the
Frequency Counter Display and verify a frequency reading of 35 MHz.
2.
Set the UUT to the Generate FM Mode and select the Gen/Mon Mtr Display. Turn the Code Synthesizer
and Ext Modulation sources OFF. Select the Narrow Band Mode and adjust the 1 kHz Level Control for
a 5kHz FM deviation reading. Connect the Mod Out Jack to the Counter Input Jack of UUT. Select the
Frequency Counter Display and verify a nominal frequency reading of 1 kHz.
5-137.
DVM
1.
Maintaining the same conditions as in paragraph 5-136.2, select the DVM Display and the AC Mode on
the display. Verify a DVM reading of 0.707 vrms ±0.04 vrms.
2.
Select the DC Mode and verify a near zero volt DC reading.
5-138.
Scope Mode
1.
Set the UUT to the Scope AC display mode and connect the scope vertical input jack to the Mod Out
Jack. Enable the internal 1 kHz modulation source. Verily the operation of each position of the vertical
input range switch and the vertical vernier gain control.
2.
With the same connection as in paragraph 5-138.1, verify the operation of each position of the
Horizontal Control and the Horizontal timebase vernier.
3.
With the Horizontal Control set to the External Mode, connect the External Horizontal jack to the Mod
Out jack. Verify a horizontal line whole length is variable with the Horizontal Vernier.
4.
Connect the Vert In jack to the Mod Out jack on the UUT. Set the vert and horizontal controls for a
convenient display. Verify that a steady sync is obtained in either the Norm or Auto modes and that the
point of triggering is adjustable with the level control. Remove the input signal and verify no horizontal
sweep in the Norm mode and the presence of a horizontal sweep in the Auto mode.
5-139.
SINAD Meter
1.
Set the UUT lor the Generate FM Function, Narrow Band Mode, and the Tone Memory Display. On the
Tone Table set Tone A for 2000.0 Hz.
2.
Select the Gen!Mon Mtr Display and the Tone A Cont Modulation Mode. Turn the Ext Level and the 1
kHz Level Controls OFF. Adjust the Code Synth Lvl Control for an FM deviation ol1.88 kHz as read on
the CRT display.
3.
Without disturbing the Code Synth Lvl Control, turn the Code Synthesizer OFF. Turn ON the 1 kHz
Level Control and adjust for an FM deviation of 7.5 kHz on the CRT display.
4.
Connect the Mod Out Jack to the SINAD Input Jack on the UUT. Verily a SINAD reading greater than
25 dB.
5.
Set the Code Synthesizer to the Continuous Mode and verily a SINAD reading 12 dB ±1 dB.
5-36
5-140.
Scan Mode
1.
Set the UUT for the Gen/Mon Mtr display. Verify the proper operation of each of the RF Scan switch
positions.
5-141.
Generate Mode
1.
Set the UUT for the Generate FM Mode at 200 MHz and select the Gen/Mon Mtr display. Verify an RF
level output display on the CRT.
2.
Connect the RF millivoltmeter with a 50 ohm termination to the RF In! Out Jack on the UUT. Set the RF
step attenuator to the 0 dB position and adjust the Variable Level control to obtain a displayed output
level of +13 dBm. Verify that the RF millivoltmeter reads +13 dBm ±2 dBm.
3.
Repeat paragraph 5-141.2 except at a center frequency of 800 MHz.
4.
Increase the RF Step Attenuator setting in 10 dB increments and verily that the displayed RF level
decreases in 10 dB increments.
5.
Set the Code Synthesizer Modulation Switch and the Ext Level Control to their respective OFF
positions. Select the Narrow Band mode and adjust the 1 kHz Level Control lor a 5 kHz deviation
reading on the CRT display. Verily a 1 kHz tone at the speaker output.
6c
Connect the Modulation Meter to the RF ln!Out Jack on the UUT. Set the Modulation Meter for a
deviation display of
5
kHz ±250 Hz.
7.
Select the Wide Band mode on the UUT and verify that the CRT displays a deviation of 20kHz. Also
verify that the Modulation Meter shows a peak deviation of 20kHz ±1 kHz.
8.
Select the Modulation Display on the UUT and verify a peak-to-peak modulation display of 40kHz ±2
kHz.
9.
Select the Generate CW Function and verify that no modulation is present on the CRT.
10.
Set the UUT for the Generate AM Function, the Gen/Mon Mtr Display, and adjust for an RF output level
of 0 dBm. Adjust the 1 kHz Level Control for a 50% AM reading on the CRT. Verify that the Modulation
Meter reads 50% ± 10% AM.
11. · Select the Modulation Display and verify a low distortion 1 kHz sinewave.
12.
Set the UUT lor the Generate SSB!DSBSC Function and verify a low distortion 1 kHz sinewave on the
CRT.
13.
Set the UUT for the Generate SWP 1-10 MHz Function and the Scope DC Display. Verily a horizontal
trace and a center frequency display on the CRT.
14.
Set the UUT lor the Generate SWP 0.01 - 1 MHz Function and verify the same results as paragraph
5-141.13.
5-37

Advertisement

Table of Contents
loading

This manual is also suitable for:

R-20028

Table of Contents