Fluke 93 - Page 135

CORRECTIVE MAIMTENANCE
7-9
7. 1.6- 3 Test point signals.
TTie digital A1 PCB
Is
provided
wltti test points, marked:
"TP’* See figure 10.1: A1 PCS layout
(component side).
These can be used to check correct
furtctloning of the PCB.
All
measurements are made In the default MASTER
RESET condition (start the measurements In the
ScopeMeter
using
MASTER RESET).
A MASTER
RESET Is performed as fellows:
1 . Remove all signals
from the ScopeMeter.
2. Turn off the
ScopeMeter
3. Hold down the LCD
key and press the ON/OFF key simultaneously.
Two beeps are audible,
and
all volatile memories
(RAM with battery backup) are reset.
The ScopeMeter Is automatically
set
to the METER
mode.
Use
another oscilloscope with high Input Inpedance
and 10:1 probe to measure the
signals on the
test points.
See table 7.1:
Table 7. 1. Overview
on Test Points on the digital A 1 PCB.
Logic O=0V, Logic 1=+5V
TP Name
Scope Freq.
Data
H/L/A
Description
207 Y40
jTjvin
^rLTLRj
'
595 Hz A Output
40,
D1404
20B
Y120
n n n mi
. .
krmj ni
595 Hz A
OUput120, D1406
209 Y200
1
—1
595 Hz A
Output 200, D 1407
210 X40
II 1 1
595
Hz
A Output
40,
D1401
211 X120
J
1
1
]
595
Hz
A Output 120, D1402
212
X2O0
1 1 r
1
595 Hz A
Output 200, D1403
213 WEN
...U .
U U . .
A Write Enable
Not point 10 of
D1203
214 REN
jirwirii".. ..
A Read Enable Not point
11 of
D1203
216 TEST1
'
0 H TEST
1/analog charnel
3,
point 16
Of D1 201
217
219
TEST2
ON.OFF
muiTL
12.1 kHz
-
0
A
L
TEST
2/timer 2 dock, point
64 of
D1201
ON OFF/high speed input
0.2,
point 53 of D1201
221
POWER ON
1
0
H POWER ON