JVC Model 200 Projector User Manual


 
Chapter 2---System Description
Generation of focus voltage (G3) for all three CRTs (RGB)
Generation of screen (G2 supply-Black Level) voltage for all
three CRTs
Generation of G1 supply (Blanking) voltage
Dynamic focus amplifier using H and V parabolas
External ON/OFF and generation of /HV_OK signal
The High Voltage Power Supply I/O diagram (Figure 2-5) and the
list of inputs and outputs (Table 2-1), provide an understanding of
the operation of the HVPS to allow the technician to perform
module level troubleshooting.
ARC GND
G2 SUPPLY
G1 SUPPLY
/HV OK
T O C R T S V I A V A B
R FOCUS J58-1
G FOCUS J59-1
B FOCUS J60-1
T O C R T S
R ANODE J58-1
G ANODE J59-1
B ANODE J60-1
T O C R T S VIA VAB
H PARABOLA
FROM CD BOARD
V PARABOLA
+80V
FROM LVPS
+15V
-15
/HV ENA (/VA_OK)
H VPS_SYNC
FROM RTG
J45
5
11
J44
J45
1
3
14
8
9
10
12
6
13
(From VPB)
HIGH
VOLTAGE
POWER
SUPPLY
Figure 2-5. High Voltage Power Supply, I/O Diagram
The HVPS Input/Output
This section provides a comprehensive description of the inputs to
and outputs from the HVPS. The I/O descriptions are arranged by
the source/destination of the signal. The format used is such that
the assembly communicated with is used as the primary heading
of each output. Input refers to an input to the HVPS. Output refers
to an output from the HVPS. In each case the signals direction is
noted.
Table 2-1. High Voltage Power Supply I/O signals
Raster Timin
g
Generator PCB
INPUT DESCRIPTION
Model 200 Service Manual 2-11