HP 8112A Operating, Programming And Servicing Manual page 218

Period Generator
1 0.3-1 6 Servicing the Timing and
Slope Generators
Table 1 0.3-9. U 1 0 1 Mode Decoder truth table
CTRL Mode UlOl/9 UlOl/6 UlOl/5 UlOl/16
Mnemonic
Off
PERC
DELC
WIDC
HILC
Area
The level check output
mode and HIGH during self test .
To check operation of the Ext. Input Circuit:
1 . Set up the HP 8 1 12A as follows:
Mode
Trig Slope
Trig Level Pot
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
Figure 1 0.3-8. Period Generator Input pin 7
To check the operation of the Period Generator:
1 . Set the HP 8 1 12A to RCL 0
2. Check the ramp signal at pin 20 of U200 against Figure 10.3-9.
(ACO)
(AC2) (ACl)
L L
L L
L H
H
L
H L
U131/2 U130/10 U 130/9 U503/1
( )
LCO on pin UlOl/16 is LOW in normal
Trig
f
Mid-range
--.J
EXT . PE R .
L
H
L
H
L
J.-­