M aintenance—T yp e 3 2 4
Sweep Generator Troubleshooting Chart.
Initial setup:
Display is obtainable in EXT HORIZ mode; VOLTS/DIV set at 5 DIV CAL;
TIME/DIV at .5 mS; POSITION controls *'inTI and centered; POWER — ON; VARIABLE controls at CAL; TRIGGER at + AUTO; Trie/
Horiz Coupling switch at I NT — AC.
>
2 V
square
wave present at
Q263-C
No
Check
Trigger
circuit
Yes
Vertical line or
square wave on
CRT
(use POSI
TION controls)
No
~ 0.8 V square
wave present at
Q 343 base
No
Yes
Yes
Unblank
or CRT
ckt
Square- wave
on CRT
No
Vertical
line on CRT
Yes
Yes
Retrace
lines show
Yes
across
0.5 V
D303
Yes
0.5 V
at Q 305-C
Yes
ZZ5
V
at Q329-E
Yes
No
» 10 mV
across D303
Yes
4- 0.2 V
at Q 305-C
Yes
No
Vertical line
on right
Yes
Yes
^ 5 V
sawtooth
N o M i l l e r
~ 5 V DC
at Q329-E
circuit
y
at Q 326-C
Yes
Yes
Horiz Amp
circuit
Fig. 4-6. Sweep Generator troubleshooting chart.
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