HP 54501A - Page 86

HP 54501A
SERVICE
6-21 . Removal and
Installation of System Board
Assembly
The effects of
ELECTROSTATIC
DISCHARGE may damage electronic com-
ponents .
Use grounded wriststraps
and mats when servicing the System
Board
Assembly .
1 .

Disconnect power
cable .
2 .

Remove
the six screws from top and
the two screws from each side of
instrument .
3 .

Lift
top
cover off .
4 .

Detach line
filter cable, W7, from Power Supply
Assembly .
5 .

Remove do
power supply cable, W1 .
6 .

Remove
the two PCB (printed circuit board)
retainers from right front and
rear
corner of Power Supply Assembly
.
7 .

Remove
Power Supply Assembly by sliding out
through side of instrument .
8 .

Disconnect
fan cable B1 W1 from System Board
Assembly .
9 .

Disconnect
keyboard cable, W5,and HP-IB
Cable, W4, from System Board
Assembly
.
10 .

Remove rear panel by removing the
eight screws securing it to
instrument
and lifting off . Refer to previous
paragraph Removal and
Installation of Rear
Panel , if necessary .
11 .

Carefully place instrument
in front-panel-down position or on
its side and
remove the EIGHT
#10 TORX e screws on the
bottom of the instrument that
secure
System Board Assembly to cabinet
.
12 .

Remove the four 5/8
inch nuts holding System Board Assembly
BNCs to
front panel .
13 .

Slide
System Board Assembly out of
cabinet through rear of
instrument .
14
.

Replace System
Board Assembly by reversing this procedure
.