Agilent Technologies 5517B Operation And Service Manual page 46

+15VFUSE(F1)
Figure 5-1. A3 Controller/Reference Board, Jumpers, Test Points, and Adjustment Locations
5-20. Procedure: Before measuring the laser tube current, observe the safety precautions in paragraph 5-4, and then
proceed as follows:
a. Disconnect laser head from system power supply. If procedure is performed at test bench, simply turn
power supply off.
b. Remove the laser head covers by following the procedures outlined in paragraph 8-57.
c. Set HEATER (JMP7) jumper to the OFF position. Set all other test jumpers to their left-most positions.
d. Set the milliammeter to the 10 milliampere range.
e. Clip the HP 428B probe around the red (Anode) High Voltage Power Supply wire located underneath
the laser tube (See Figure 5-2). The arrow on the milliammeter probe should point away from the
supply. Keep the probe as far as possible from and perpendicular to the magnet assemblies. It may be
necessary to prop up the probe to achieve the perpendicular orientation.
f. On the Milliammeter, adjust for zero indication. If zero indication cannot be obtained, degauss the
probe as directed on the back of the milliammeter.
After the zero setting has been made on the Milliammeter, do not move the
probe, this will affect the zero setting.
g. Apply power to the system power supplies
READY LED will remain OFF. LASER LED illuminates followed almost
immediately by emission of laser light.
h. Observe the laser tube current reading. A reading of 3.5 mA ±0.1 mA musts be measured. If not, the
high-voltage power supply must be replaced with a new power supply.
TEST POINT 1
(GROUND)
TEST POINT 11 A3R16 (SET TEMP)
(HEATER SENSE)
NOTE
NOTE