Tektronix DM 5010, Инструкция по эксплуатации

Страница: 225 / 347

Adjustment Procedure— DM 5010
Preparation
Before adjustments can be performed, the internal CAL
jumper must be repositioned. For access to the jumper, re­
move the instrument’s left side cover by turning the two
plastic fasteners. The jumper is located in the lower rear
corner of the CPU board (A14). See Fig. 10-1 in the pullout
pages of this manual. Reposition the CAL jumper, P1132, to
the CAL position. Also, make certain the 50-60 Hz jumper is
positioned to match the power module line frequency. This
jumper is also located on the CPU board. Replace the side
cover.
Since the DCV and OHMS adjustments are more sensi­
tive to temperature variations, these adjustments are made
with the instrument operating in the power module. Install
the DM 5010 in the power module, turn on the power mod­
ule and allow warm-up time before beginning adjustments.
WARNING
Dangerous voltages may be encountered in the foi­
lowing steps. Caution must be exercised. Do not con­
tact the output connectors of the voltage calibrator,
the input terminals of the DM 5010, or the internal cir­
cuitry of the DM 5010. Also, do not contact the inter­
nal adjustments, since they may be at the DM 5010
input potential; use only an insulated adjustment tool
for adjustments.
Preliminary Control Settings
DCV
NULL
LOW FREQ RESPONSE
RANGE
TRIGGER MODE
CONVERSION RATE
CALCULATIONS
REAR INPUT
on
off
off
STEP (200 mV range)
RUN on
FAST off
all off
off
e. Set the range and FAST button as shown in the next
line of the table.
f. Repeat parts c through e for each succeeding line in
the table.
g. Remove the shorting plug.
DM5010 ! DM5010 Display
Table 6-2
DCV OFFSET CALIBRATION FACTORS
Range FAST Press
wiaµiay
Reading
200 mV off ENTER
0.00 mV
on
ENTER 0.0 mV
2 V on
ENTER .OOu V
off
ENTER .0000 V
20 V
off ENTER 0.000 V
on
ENTER 0.00 V
200 V
on ENTER
0.0 V
off ENTER
0.00 V
1000 V
off ENTER
0.0 V
on
ENTER
I
0. V
2. Adjust the DCV Gain Calibration Factors
a. Set the DM 5010 controls to the preliminary control
settings.
b. Connect the de voltage calibrator through appropriate
cables and connectors to the DM5010 HIGH and LOW
connectors.
c. Set the de voltage calibrator output to 190 mV de.
1. Adjust the DCV Offset Calibration Factors
a. Set the DM 5010 front-panel controls to the prelimi­
nary settings.
b. Connect the dual banana shorting plug between the
DM 5010 HIGH and LOW INPUT connectors.
d. Press ENTER.
e. CHECK—that the display reads as shown in Table
6-3, ± 1 in the LSD.
f. Set the FAST button as shown in the table.
c. Press ENTER.
g. Press ENTER.
d. CHECK —that the display reads as shown in Table
6-2, ±1 in the least significant digit (LSD).
h. CHECK—that the display reads as shown in the ta­
ble, ± 1 in the LSD.
6-3