Tait T850 II Series, Service Manual

Page: 265 / 370

M850-00
T858/859 Fault Finding D4.1
Copyright TEL 31/09/98
4 T858/859 Fault Finding
Caution:
This equipment contains CMOS devices which are susceptible to dam-
age from static charges. Refer to Section 1.2 in Part A for more infor-
mation on anti-static procedures when handling these devices.
The following test procedures and fault finding flow charts may be used to help locate a
hardware problem, however they are by no means a complete fault finding procedure.
If you still cannot trace the fault after progressing through them in a logical manner,
contact your nearest Tait Dealer or Customer Service Organisation. If necessary, you can
get additional technical help from Customer Support, Radio Systems Division, Tait Elec-
tronics Ltd, Christchurch, New Zealand (full contact details are on page 2).
Refer to Section 5 where the parts lists, grid reference index and diagrams will provide
detailed information on identifying and locating components.
The following topics are covered in this section.
Section Title Page
4.1 Visual Checks 4.3
4.2 Component Checks 4.3
4.3 DC Checks 4.3
4.4
4.4.1
4.4.2
RF Checks
General
PA Faults
4.4
4.4
4.4
4.5 Voltage Chart 4.7
4.6
4.6.1
4.6.2
4.6.3
4.6.4
4.6.5
Fault Finding Charts
T858 PA
T858 Power Control
T859 PA
T859 Power Control
T859 Fan Control Circuitry
4.8
4.8
4.9
4.10
4.11
4.12
4.7 Replacing PF Power Transistors 4.13
4.8 Removing The PCB From The Heatsink 4.15
Figure Title Page
4.1
4.2
T858/859 Test Break Point Location
Typical Transistor/Capacitor Spacing (Not To Scale)
4.5
4.13