HP 5501A Operating And Service Manual page 248

Table 6-4. English/Metric Pulse Output Electronics System Troubleshooting (Cont'd)
Example :
With no deadpath switches set (all switches down), the frequency counter should detect the
following counts:
English Units (Compare with chart above)
1.6 MHz output
44 [I761
800 kHz output
65 [260]
(Number in brackets represents total
equivalent A-Quad-B counts output
from 10763.)
TEST
B:
10755 COMPENSATION INTERFACE TEST
Equipment needed
:
logic clip or logic probe
10756 manual compensator
Test procedure: Dial in thurnbwheel setting on chart
Press update
Tie U2 (11) and U2 (8) to ground, using E-Z mini test hook or equivalent (to enable
tri-state output buffers)
Compare signal levels with those given on chart (Table 6-4f)
If
signal levels do not correspond, check BCD input lines (Table 6-4g)
Table 6-4f: Compensation Interface Output
OUTPUT LINES
THUMBWHEEL
SWITCH
SETTING
000.0
876.5
212.1
U8
pins
7 5 3 9 1 1 1 3
0 1 1 0 1 1
1 0 0 1 0 0
0 1 1 1 0
1
Table 6-4g: Compensation lnterface Input
INPUT LINES
U12
pins
5 7 3 9 1 3 1 1
1 1 0 1 1 1
0 1 1 0 1 0
1 1 1 0 1 1
THUMBWHEEL
SWITCH
SETTINGS
000.0
876.5
212.1
U16
pins
3 5 9 7
0 0 0 0
1 1 0 1
1 0 0 1
U17
Pins
9 10 1 15
0 0 0 0
1 0 0
0 0 1 0
U13
Pins
9 10 1 15
0 0 0 0
0 0 1 1
0 0 0
U9
Pins
9 10 1 15
0 0 0 0
1 0 1 1 0 0
1 0 0 1 0
U5
Pins
9 10 1 15
0 0 0 0
1 0 1
0 0 0
1