Horizontal Deflection Circuit - Philips FIMI Field Support Manual

Horizontal Deflection Circuit (figure 8.3)
a. Connect +5VDC to the junction of R51 and R53 wiper, connect -VE rai
1
to
Xl-al. Connect character generator output HS to Xl-bl and ground to Xl-al.
b. Connect oscilloscope probe (Xl) to junction of U51 pin 5 output and R58, set
set the following switch positions:
Hori zonta
1
Vertical
Coupling
lOuS/div
lV/div
DC
c. Switch on supply and character generator wait 30S warm-up period.
Observe waveform on oscilloscope (see figure 8.3).
I---
t
2 ----i
i - - - - - - - - - - 1 1 - - --
Figure 8.3 HORIZONTAL SYNC. TIMING
d. Adjust PHASE POT R53 for tl
=
50uS. Check that t2
=
18uS and V
=
4,2V.
e. Switch off supply and character generator on completion of adjustment,
disconnect the +5VDC test supply from the PCB.
8-6
FIMI MON 12
11
/15
11
8305