HP 8112A Operating, Programming And Servicing Manual page 219

Figure 10.3-g. Period Generator ramp signal pin 20
3. Check the trigger output signal at pin 21 of U200 against
Figure 10.3-10.
4. Check the signal being sent to the delay generator IC220 at TPl
against Figure 10.3-10.
OUTPUT ON PIN2 1
OUTPUT TO DELRY
GENERRTOR ON TPl
Figure 10.3-10. Period Generator output signals
5. Check the period generator operation against Table 10.3-10 and
Table 10.3-11:
Table 10.3-10. Period Generator Operation
Mnemonic
5
PERC
2
E R P
10
11 to 18 LD7 - LDO
R212
PVC
6 . Verify that voltage at U200 pins 1 , 4 and 5 are at virtual ground
- 4 0
min.
7 0 n s
5 0
.
Description
Period control voltage input
Period error output signal
Period input store select
Data to be latched into
the input store of U200
Period vernier current
Servicing the Timing and 10.3-17
Slope Generators
%
State
L
L
See Table 10.3-l
See Table 10.3-2
See Table 10.3-11