8-289.  REMOVAL PROCEDURE. Remove the 
A2 
board 
as 
follows: 
a.  Remove cover 
as 
described under paragraph 8-282. 
b.  At bottom of  instrument, remove two front feet and two screws 
(0515-0890) in Front Panel Assembly 
frame. 
c. 
At top front of  instrument, snap-off the plastic trim strip 
(MP11,5040-7202) with a small flat blade 
screw driver. 
d.  Remove two screws (0515-0890) attaching the Front Panel 
(MP19,05334-00019 
- 
Standard Front 
Panel; 05334-00024  Option 
030 
Front Panel) to the Front Frame (MP23,05334-20201). 
e.  Remove two Trigger Level Knobs (MP25,0370-1005). 
f. 
Remove three "fancy" BNC nuts 
(0590-1251) that secure the INPUT A, B,  and 
ARM 
connectors. 
g. 
Now, separate the Front Panel Assembly from the chassis. 
h.  Unplug 
A2 
Front Panel Board from A1 Main Board. 
i. 
The 
A2 
Board 
is 
now accessible. 
8-290. 
INSTALLATION PROCEDURE. To install or replace 
A2 
Front Panel Board, perform the following: 
a. 
Align 
A2 
board with back of  Front Panel and snap into place. There are four places to hold the 
board in place. Insure these are set. Adjust board to center 
keycaps. 
b. 
Secure the two Trigger Level potentiometers (pots) using one flat washer, lock washer and nut for 
each pot. Hand start the nuts. Tighten using 5/16 spin-tight. 
c. 
Using a small flat blade screwdriver, set the Trigger Level pots to full counterclockwise positions. 
d.  Place one knob on one of the pots, aligning the marker with the 
"R" 
in 
ARM 
on the front panel. 
e.  Secure the knob by using the proper 
allen wrench on the set screw. Tighten. Repeat steps d and e for 
the other pot. 
f. 
Place Front Panel into the Front Frame, pushing up and aligning the BNCs with the front holes and 
pushing the panel up to get over the Front Frame edge. 
8-291.  REMOVAL AND INSTALLATION OF FRONT PANEL RED WINDOW. The seven-segment dis- 
plays can be replaced through the front panel by  removing the red window from the panel. To remove the red 
window, perform the following: 
a.  To remove the red window 
(MP24,05334-40002), place a small flat-blade screwdriver between the 
window and the front panel along the bottom edge and gently press up and out, then pull out the win- 
dow. 
b. 
To install the red window, set window into panel, top edge first (make sure the rubber foam gasket, 
05334-00011 is in place), then press down on window gently and snap the bottom edge into place. 
8-292. 
TROUBLESHOOTING 
8-293. 
The troubleshooting section is divided into two parts: (1) Signal Tracing and (2) Signature Analysis. 
8-294.  Other troubleshooting aids are the Operational Verification Tests found in Section IV of  this manual. 
They provide a good place to start the search for a 
HP 
5334B 
failure. These tests consist of power-up diagnostic 
checks as well as functional checks of  all the Counter circuit blocks. 
HP 
5334B 
- 
Service Manual 
8-39