Philips 50 T Series, Руководство по обслуживанию

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Chapter 8 - RF Bench Repair
RF Bench Repair
Introduction
RF Bench Repair should be performed when the low-frequency sections of
the Series 50 T Transmitter and Receiver have passed the tests in the
Troubleshooting Flowcharts Chapter 4 with no problems. RF associated
Transmitter and Receiver problems should be identified and resolved using
the RF Bench Test.
Caution
Static electricity will damage sensitive electrical circuitry. Ensure you are
adequately grounded before touching any circuit board or its associated
components.
What You Need
The following equipment is required to perform the test and repair:
The goal of the RF Bench Test is to find out which of the following sections is
defective:
Transmitter VCXO (M1400-6xxxx)
Receiver Preamplifier Board (M1406-60560)
Receiver Assembly (M1402-6x30x)
Receiver VCXO (M1402-61xxx)
If the operating range is decreased or no transmission is possible, the
following tests given in this chapter should be performed.
Equipment Requirements Example
Oscilloscope >10MHz, 100 mV min HP54601A
Active Probe 500 MHz (min.) HP1120A
Spectrum Analyzer 100 Hz to 500 MHz (min)
Freq. Accur.:<2ppm HP8568B
Signal Generator 500 MHz (min.) HP8640B
2 BNC Cables 50 Ohms
0.7 to 1.5m long HP10503A
BNC Adapter 50 Ohms 1250-0080
AC coupler 0.18uF, 200V 10240B