General Service Information - HP 8447D Operation And Service Manual

WARNING: These servicing instructions are for use by qualified personnel only. To avoid electrical
shock, do not perform any servicing unless you are qualified to do so.
WARNING: The opening of covers or removal of parts is likely to expose dangerous voltages.
Disconnect the instrument from all voltage sources while it is being opened.
WARNING: The power cord is connected to internal capacitors that may remain live for 10 seconds
after disconnecting the plug from its power supply.
Test Equipment and Accessories Required For Troubleshooting
Test equipment and accessories required to troubleshoot the amplifier are shown
in Table 4. Test instruments other than those listed may be used provided their
specifications meet or exceed those listed in the table.

General Service Information

The part reference designator is the assembly designator plus the part designator.
(Example: A1R9 is R9 on the A1 Power Supply Assembly.) Refer to the parts list
of the desired model number for the specific component description for ordering
parts.
Additional technical assistance may be obtained by contacting your local Hewlett-
Packard sales and service office. Some of these offices are listed in Table 13.
Troubleshooting Procedure
First check the input and output cables. Isolate the trouble to the amplifier(s) or
power supply by checking the
from C2. If the voltage is present, replace the amplifier (re-attach the red wire to
C2). If voltage is not present or incorrect, check the power supply. The voltages
shown are typical with the amplifier(s) disconnected from the power supply.
Equipment:
Digital voltmeter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 3440A/3444A
Cable assembly (w/test clips). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 10501A
Adapter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 10111A
DRAFT
+
20 volts at XA1-14 after removing the red wire
Operation and Service Manual
Parts and Service
53