9-36
September 27, 2000
68P81093C75-O
Required Test
Equipment
The following test equipment is required to properly tune the
preselector assembly:
•
RF Signal Generator: Motorola R2600
Communications Analyzer, R2001
Communications Analyzer (see note), or
HP8656A signal generator (or equivalent)
•
Dip/Peak Monitor: HP435B Power Meter (or
equivalent) with HP8484A sensitive power head,
Boonton Model 92E with BNC input, or R2001/
R2600, using the spectrum analyzer function.
•
Torque Driver, capable of delivering 12 in. – lb. of
torque, and 10 mm deep well socket.
•
Tuning probe: Motorola Part number
0180763D22, part of TRN7799A tuning kit.
•
Flat-blade screwdriver
NOTE: The R2600 Communications Analyzer can both
generate and measure simultaneously. The R2001
may be used for either the generator or monitor
function, but not both simultaneously. When using
the R2001 as a signal generator, RF signal must be
taken from the antenna port.
VHF Tuning Procedure
Calculating Proper
Alignment Frequency
Use one of the following two methods to calculate the alignment
frequency to be generated by the signal generator.
For stations with a single receive frequency, calculate the frequency
of the alignment signal as follows:
Step 1. From the site documentation or the RSS, determine
the station receive frequency.
Step 2. If the frequency is
≤
148 MHz (Range 1) or
≤
156
MHz (Range 2), subtract 250 kHz. Otherwise, note the
actual frequency.
Example: If the station receive frequency is 134.575
MHz (Range 2), subtract 250 kHz, since the frequency
is less than 143 MHz.
134.575 MHz - 250 MHz = 134.325 MHz
