Motorola MTR2000 T5544 Instruction / Field Service Manual page 323

6.
Verifying Insertion Loss
1.
Connect test equipment as
shown.
2.
Observe and note the level in
dBm as shown on the millivolt-
meter.
3.
Connect the duplexer cable as-
sembly and test equipment to the
duplexer as shown.
4.
Observe and note the level in
dBm as shown on the millivolt-
meter.
5.
Subtract the absolute number
noted in Step 2 from the number
noted in Step 4. The difference
should be less than 1.3 dB to
meet specification for Insertion
Loss.
6.
Repeat Steps 1 to 5 for Low-
Pass/High Notch cavities with the
following exceptions:
a)
Set Frequency Generator for
Rx or Tx frequency,
whichever is LOWER
b)
Connect Signal Generator to
Low Pass duplexer input
(cavity #1)
c)
Connect terminator to cavity
#6.
Figure 9.
68P81085E16-B
09/30/05
6dB In-line
pad (50Ω)
1 2 3 4
Terminator
6dB In-line
pad (50Ω)
VHF Duplexer Field Tuning Procedure (Continued)
Boonton 92E RF
Millivoltmeter
Range set to +10dBm
HP8656B Signal Generator
UG349A N-to-
BNC Connector
Frequency set to Rx or Tx frequency,
whichever is HIGHER.
Output Level set to +10dBm.
HP8656B Signal Generator
5 6
VHF Duplexer Module
Boonton 92E RF
Millivoltmeter
15