Hitachi 61HDX98B Manual page 104

DEFLECTION TROUBLESHOOTING (DRIVE SIGNAL COMPARISON)
The output from IH01 Pin 12 is then routed to IH02
Pin 10. Internally a signal is produced that actually
drives the High Voltage Horizontal Output transistor.
The output waveform is produced at Pin 7
DM-1
Module
23
3
SIGNAL PWB
I001
Slave
Q007
Micro
53
Power ON
Driver
I702
1
VRef-In DVcc
I701
5V Reg. 1
I703
Comp. 8
HORIZONTAL POWER SUPPLY GENERA-
TION CIRCUIT EXPLANATION:
It is important to remember that the Power Supply also
plays a roll in the deflection circuit. A HVcc switch is
used in the power supply, QP09. QP09s emitter is sup-
plied with A12V. When the Power ON command is
20
generated from I001 pin 55 (high), the power on driver
Q007 is turned on. A LOW is produced at it's collector
and routed through the PQS1 connector pin 3. This
low is then routed to the PQD2 connector pin 5 to the
base of QP08, turning it ON and supplying 12V to the
connector PDD1 pin 1 and 2. This 12V then is routed
to I702 pin 1, I701 pin 1 and I703 pin 8 on the sub de-
flection PWB. This IC in turn generates the Horizontal
Drive signal used in the comparisons above.
SUB POWER PWB
PQS1
3
SUB DEFLECTION
PWB
Figure 21
PQD2
A12V
QP08
5
PDD1
1
2
DEFLECTION
PWB
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