HP 8112A Operating, Programming And Servicing Manual page 221

Note
Width Generator
Table 1 0.3-12. Delay Generator Operation
U220 Pin Mnemonic
5 DELC
2 ERD
10 DIC
11 to 18 LD7 - LDO Data to be latched into
R226 DVC
(
6. Verify that voltage at U220 pins 1 , 4 and 5 are at virtual ground
min. -40 m V max. 0 V
Delay Vernier Current can be checked by measuring the voltage
across R226.
7. Set HP 8 1 1 2A PER to 20 ms
8. Check the Delay Generator levels against Table 1 0.3-13
Table 10.3-13. Delay Generator Signal Levels
DEL Setting Voltage across R226
1 . Set up the HP 81 12A as follows:
RCL 0
DEL
650 µs
DBL 200 µs
2. Check the input signal from the delay generator at TP2
U240 against Figure 1 0.3- 13.
I
i.._ DBL
I
I
J.---
DEL 6 5 0 u s
Figure 1 0.3-13. Width Generator Input
3. Check the ramp signal at pin 20 of U240 against Figure 10.3- 14.
Description
Delay control voltage input
Delay error output signal
Delay input store select
the input store of U220
Delay vernier current
)
+0.16 v
1 ms
5 ms +0.003 v
ms -0.02 v
9.99
OT
2 00u s
----./
Servicing the Timing and 1 0.3-1 9
Slope Generators
State
L
L
See Table 10.3-1
See Table 10 .3-2
See Table 10.3-13
(
pin 7 of
L
_ _