HP 8481A - Specific Repair Procedures; Bulkhead Replacement and Repair

08481-90049
HP 8481A/82 A/83 A
are finished, the appropriate SWR test setup. (See table 4 for system
specifications.)
K you repair power sensors often and have the proper calibration
systems, bulkhead repair can be more economical than
replacement.
If
Note
A2 Input Amplifier Assembly Printed Circuit. If the
A2 Input Amplifier
Assembly is at fault, replace it. Replacing the A2 Assembly is usually
less costly than than the time it takes to troubleshoot
and replace
faulty components. For those who wish to troubleshoot,
use figure 4,
“Power Sensor Schematic Diagram”.
Bulkhead Replacement
Read repair strategy, above. Bulkhead replacement differs from repair
in that no special tools or skills are required other than those needed to
do the FET balance adjustment.
Procedure
1. Order your new or restored A1 Bulkhead Assembly
from table 5,
“Replaceable Parts”.
2. Follow the dissassembly and reassembly procedure for bulkhead
removal and replacement located near the end of this manual.
3. Check the FET balance using the procedure that precedes the parts
list. If you did not disturb the wires, it is likely that no adjustment
will be necessary.
4. Place the new calibration sticker on the power sensor cover.
Bulkhead Repair
Read the repair strategy, above. Before beginning repair, inspect the
center conductor and outer conductor with a magnifying glass. If you
have any burrs or scratches visible on the connecting surfaces you
should complete the entire procedure below or replace the bulkhead.
If your connecting surfaces are acceptable, repair your bulkhead by
replacing cartridge (A1MP16) starting with step 9. Do not attempt
repair without the following equipment.
Equipment
Power Sensor Calibration System . . . HP 11760S
Type N Connector Gage
Precision 7mm Connector Gage
(for Option 001)
SWR Test Set
Rebuilding the Bulkhead.
1. Refer to the parts list and figures 6, 7, and 8. Order the internal
type N bulkhead parts AlMPl through A1MP12. (HP 8482A and
8483A do not use A1MP12 polyiron slug. The precision 7mm
85054-60024
1250-1875
See table 4 for specifications.
18