HP 5065A Operating And Service Manual page 127

-INCORRECT SIGNAL -
- CORRECT SIGNAL
- Check Q19, Q20, T l ,
and associated circuitry.
Check CR32, CR33,
and associated components.
Check C31 and C32.
Check Q23 and
-associated compo­
nents in base
circuitry.
,— Check R79
YES
Check DC voltage
r - at Q22(C). Should -
be approximately
15V.
NO
Remove Y l ,
— M e a s u r e voltage -
at T P 1 with high
impedance. DC
voltmeter should
be 6V ± .5V.
NO like
O
NO
YES
Disconnect J2
and connect
counter to J3.
Wait 5 minutes
and note fre­
quency; connect
■—junction at R71
and R72 to ground.
Frequency should
change 700 Hz.
L
Check R76,
Q22 & its base
bias circuitry.
NO
Measure DC
voltage at Y l -
CR27 junction
■ alternately con- —
necting R71, R72
junction to ground.
Voltage should YES
change 6 Vdc.
Check continuity
I—from CR27 thru
LI, L2, L4, &A1S2
- O K - - Replace CR27
NO
r
Check for
leakage
around CR27
Replace
"CR27
NO
Remove Yl
. and repeat
R79 voltage
measurement.
NO
YES
YES
OTHER•
_Check A1S2 _
with ohmmeter
YES
L
Check CR32,
CR33 and associated
Readjust L I , L2, components in
& L4 (See A1Y1, A1L1,
s a m
P
l i n
8 circuitry.
A1L2, A1L3 A1L4 check
and replacement.)
Measure DC
voltage a c r o s s
,
O K
R79 with Hi Z _
impedance
voltmeter 0.1
Vdc or l e s s .
YES
Replace Yl
(See A1Y1.A1L1,
>—A1L2,A1L3,A1L4
check and replace­
ment. )
L
Readjust LI, L2,
& L4 (See A1Y1,
A1L1, A1L2.A1L3,
check and r e p l a c e ­
ment.