Skanti TRP 5000, Инструкция по эксплуатации

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7. REPAIR AND ALIGMENT
7.1
Introduction
Repair and adjustments on the equipment shout be preformed only by
qualified technicians, to whom this chapter is addressed. Before
attempting any repairs or adjustments, a study of Chapter 5, Technical
Description, is recommended.
7.2 Cross-Slot Srews
The cross-slot screws used to secure the printed circuit boards are
Pozidriv screws. A Pozidriv screwdriver No.1 should be used in order to
avoid demage such screws.
7.3 Locating Subunits and Components
Locations of circuit boards in the equipment appear from the photographs
on pages 8-56 and 8-59. Locations components on each circuit board
appears on the component location drawings against the respective
circuit diagrams.
7.4 Locating Faults
Fault findings, as described in section 7.5 below, is aided by test
points provided for the purpose of permitting rapid localization of
faulty circuit boardson the basis of DC measurements. Since not all
types of faults can be traced by means of DC measurements, supplementary
AC measurements with an oscilloscope may be required; see section 7.6.
To facilitate fault finding on each individual circuit board, typical
voltages are listed on the circuit diagrams.
7.5 Test Points
Several circuit boards contain one or more test points. They are small
pin-type terminals, colour coded following the standard colour code in
addition to being numbered. In the circuit diagrams, test points are
maked [TP1] , [TP2] etc., and typical voltages at the test points are
listed there.
The terminals of the circuit boards may to a great extent also regarded
as test poits. Tipical voltages are therefore also listed against
relevant terminals on the circuit diagrams.
If a voltage measured at a test point differs markedly from the listed
value it is faily certain indication that the circuit board in question
is faulty, assuming that the voltages applied to the circuit board are
the correct ones. This should likewise be checked.