Tektronix 2440, User Manual

Page: 253 / 531

Table 6-6 (cont)
Maintenance— 2440 Service
Force DAC Ranges
DAC
DAC FORCE DAC V alues/
Voltage Range Effect of
Output Output DAC Voltage After
Increasing Value
Location Cold Start
0 4095
CM 20 U640-7 1 6 5 0 /- 0 . 2 7 V
+ 4 .7 6 + 12.1 CH 2 CCD Sides 1 and
2 0 0 0 /- 0 .0 4 V + 4 .7 6 + 12.1
3 offset from 2 and 4.
2 2 0 0 /—0.10 V
+ 4 .7 6
+ 12.1
CM2E U640-8
1 6 5 0 /- 0 . 2 7 V
+ 4 .7 6 + 12.1
CH 2 CCD Sides 2 and
2 0 0 0 /—0.04 V + 4 .7 6 + 12.1
4 offset from 1 and 2.
2 2 0 0 /—0.10 V
+ 4 .7 6 + 12.1
TRN19
U661-14
2 0 0 / - 1.24 V - 1 . 3 7 + 1.36
TRN2 U631-14
HORF
U631-8 1 0 0 / - 1.30 V - 1 . 3 7
+ 1.36
JIT1
U661-1
1 700/—2.54 V
- 7 . 6 9 - 2 . 2 3 V Fast Ramp Slope
JIT2
U661-7
increases for more
counts per sec
ALVL U640-1 2176/0.09 V - 1 . 3 7 V - 1 . 3 6 V Triggers at lower point
GRAT U520-10 4095/14.66 V
0.83 Vh
14.66 V Decrease Grat intensity
U820-1 4 0 9 5 /—3.34 V
4.20 V - 3 . 3 5 V
INTN
U820-8
3160/0.78 V
- 1 . 3 7 V
1.36 V
Increases intensity
NORM U820-7 1 640/- 0 . 2 8 V
RD01 U820-14
2050/0 V
CURS (CAL) U610-3 2 0 4 8 /—0.50 - 1 . 3 7 V
1.36
U610-3 ~0 V - 0 V
Current output into
U610-4
~ 0 V - 0 V
75 fl loads
U610-6 ~ 0 V - 0 V
U610-13 ~ 0 V 0 V
U610-15
> O
2
0 V
HORF
U631-8
1 0 0 /—3.90 V -4 .1 1 V 4.09 V
Increases holdoff
DACO U650-6
2 0 4 8 /+ 0 .0 4 V
13.92 V - 1 3 . 1 5 V Unbalances DAC
DACG U660-6 3 9 2 9 /-0 .2 1 V 14.02 V - 1 3 .3 2 V
- 5 . 1 8 V 1
Uncalibrates DAC
SEach TRNx DAC output has a unique constant for each VOLT/DIV setting between 2 mV and 50 mV. Each of these constants is set
to 200 when the instrument is cold started.
"Limit at a DAC count of approximately 2000.
'DACG (DAC Gain) interacts with DACO (DAC O ffset); therefore, the DACG range can be lim ited if DACO is not centered. Changing
either DACG or DACO causes the remaining DAC System outputs to be invalid until the correct settings for DAC Gain and O ffset are
rewritten into the DAC System.
6 -4 5