Multitone FLA 872 Technical Manual page 53

CHECK TR410, L408
AND XL402.
'B'
TM1205 Issue 2
'C'
IS 455kHz PRESENT ON
TP405?
NO
IS 2nd LOCAL OSC. O/P
(IC401, PINS 1 AND 2)
>200mV?
YES
SHORT JUNCTION OF
C407/R446 TO 0V.
IS IC401, PIN 24 >3mV?
NO
IS TR403 (1st MIXER
O/P) >3mV?
REMOVE SHORT FROM
C407/R446 TO 0V.
IS 1st LOCAL OSC. O/P
NO
(TR410 COLLECTOR)
>25mV?
IS RF AT TR402
NO
COLLECTOR >3mV?
CHECK TR401,
TR 402, L401, L416.
Figure 5.7: Fault Finding Guide (Sheet 3 of 3)
YES
FL402 OR C444 FAULTY.
NO
CHECK XL401
YES
CHECK IC401
YES
CHECK FL401, L410 AND
R479 (280MHz board).
R444 (172MHz board).
YES
CONNECT TR410 BASE
NO NO
TO 0V. IS RF LEVEL AT
TR403 BASE >3mV?
YES
CHECK FL405
TLA 852/FLA 872
YES YES
CHECK TR403
AND L406.
TAG11339-1
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