HP 8508A - Page 114

Service
Designation Assembly Test Series Number
AS Processor 3500
A2 Power Supply 200
A4 Search and Lock 400
300
A3 IF Board
~
When a faulty assembly is detected, an error code in the series will appear in Display 2. However, before replacing
the suspect assembly, a check should be made of the Power Supply Levels, cables and connections and any adjust-
ments relative to the assembly. For example, an IF Assembly error may be caused by a damaged sampler; and, a
Power Supply error may be caused by a faulty Search and Lock Assembly. Specific troubleshooting information is /
given by error code series in the following pages.
Following any replacement, perform any required adjustment procedure, then the full performance test to ensure
that the instrument meets specifications.
For the adjustments, use tuning tool HP part number 8830-0024.
. NOTE: Under some circumstances, it is possible that a 4-digit error code will be displayed (although this is not
likely to happen during the normal test routine). Should this type of Error Code appear, the instrument power
should be cycled and, if the error reappears, please contact your local HP Service Office.
Disassembly and Reassembly Procedure For the Standard Instrument
Top Cover Removal
To remove the top cover from the Vector Voltmeter, follow the procedure listed below:
a. Remove the two rear feet, each of which is held in place with a Pozidriv screw.
b. Undoing the Pozidriv screw at the centre of the rear edge of the Top Cover will cause the cover to slide
back. When it is clear of the front frame it can then be lifted off.
Refitting the Top Cover
Refitting of the top cover is the reverse of this procedure.
8-4
E1089
eae @euesennnnnnnn @euneneunenna@uen