HP 8112A, Operating, Programming And Servicing Manual

Page: 218 / 406

Table 1 0.3-9. U 1 0 1 Mode Decoder truth table
CTRL Mode UlOl/9 UlOl/6 UlOl/5 UlOl/16
Mnemonic (AC2) (ACl) (ACO)
Off L L L
PERC L L H
DELC L H L
WIDC L H H
HILC H L L
Area
U 1 31/2 U130/10 U 130/9 U503/1
The level check output
(
LCO
)
on pin UlOl/16 is LOW in normal
mode and HIGH during self test .
Period Generator
To check operation of the Ext. Input Circuit:
1 . Set up the HP 81 12A as follows:
Mode Trig
Trig Slope
f
Trig Level Pot Mid-range
2. Apply a symetrical signal to the Ext. Input .
3. Check the input signal from the trigger input circuit at pin 7 of
U200 against Figure 10.3-8.
-0 . 2 V
- 1 . 5 V
--.J
EXT . PER .
J.-­
Figure 1 0.3-8. Period Generator Input pin 7
To check the operation of the Period Generator:
1 . Set the HP 8 112A to RCL 0
2. Check the ramp signal at pin 20 of U200 against Figure 10.3-9.
1 0.3-1 6 Servicing the Timing and
Slope Generators