Genius 2793 User Manual

Page of 114
Equipment Setup For Repairing The Model XX93 Monitor.
+17.1
DVM
OSCILLOSCOPE
     ISOLATED 
DUAL 1A DC
POWER
SUPPLY
CERONIX Model XX93
115
VAC
Test
Generator
or
Signal
Source
TRANSFORMER
VARIABLE
1-4VDC
12Vpp 50,E2
No DVM
320
Vpp
40,G1
0 to 30V 0 to 30V
ISOLATION
TRANSFORMER
Represents the XX93 board part number.   The parts list gives the 
CERONIX PART NUMBER which is indexed to the board part number.
{
Part numbers of the resistors on the PRA indicated by 
LTR.
PRA pin number.   To determine which PRA the pin number
belongs to, look for the nearest PRA part number on that line.
{
DC voltages are measured to GND except in the power supply
where V- is the reference.  Use a DVM for DC measurements.
CAUTION: When making measurements
on the power supply be sure that the other
scope probe is not connected to GND.
Test Point, board cross REFerence location.
The waveform is normally checked with a oscilloscope.
Vp-p
It has a P-P voltage amplitude of
{
.
Legend Description
No.
LTR.No.
X
X
X-Y VDC
X-
Y V
No
.
LTR.No
.
X-Y VDC
X-
Y
X-Y VDC
TP-REF.
Vp-p
WAVEFORM
X
X
LEGEND
BOARD PART No.
PART No. ON PRA.
DC VOLTAGE RANGE,
 USING A  DMM.
AC VOLTS
Peak to Peak
TEST POINT
ASS. REF.
Measured with scope
Sync.
USE V. or H. SYNC.
{
Measurements
are taken with
a white screen.
Hs - 5uS/div.
Vs - 2mS/div.
WAVEFORM
X-Y VDC
TP-REF.
Vp-p
Sync.
PRA PIN No.
When all else fails,
connect 20 volts to the
power supply 17 volt
line and slowly
increase the AC
voltage up to just
before the the power
supply chirps.   This is
called the smoke test.
92