Plug-In Support Assembly Removal; Ac Convertor (A3) Assembly Removal; Analog (A2) Assembly Removal - HP 3457A Service Manual

Replaceable Parts
f. Remove the Digital Assembly by raising the front edge of the board and sliding it forward.
g. T o replace the Digital (Al) Assembly, reverse the order of steps a through f.
6-27. Plug-In Support Assembly Removal
6-28. The Rear Terminal Assembly or Plug-In Assembly and Top Cover must be removed prior t o removing
the Plug-In Support Assembly. Remove the Support Assenlbly as follows:
a. Remove the Rear Terminal Assembly (paragraph 6-17) or Plug-In Assembly (paragraph 6-19) and
Top Cover (paragraph 6-21).
b. With the front panel of the instrument facing you, move the Plug-In Support Assembly slightly t o
the left t o release the locking tab, and lift the support upward.
c. Lay the Plug-In Support Assembly over the front panel to gain access t o the T o p Analog Shield.
(The Support Assembly will be supported by its cables.)
d. Remove the T o p Analog Shield. (Press the sheet metal tabs near the center of the instrument t o
release the shield, lift the shield and remove it.)
e. Disconnect connector A2-P501 and the five input wires to remove the Support Assembly.
f. T o replace the Plug-In Support Assembly, reverse the order of steps a through e.
6-29. AC Convertor (A3) Assembly Removal
6-30. It will be necessary t o remove the Rear Terminal Assembly or Plug-In Assembly, T o p Cover, and
Plug-ln Support Assembly prior to removing the AC Convertor Assembly.
a. Remove the Rear Terminal Assembly (paragraph 6-17) or Plug-In Assembly (paragraph 6-19), T o p
Cover (paragraph 6-2 1) and Plug-In Support Assembly (paragraph 6-27).
b. Disconnect the red and black input wires and connector A2-P303 from the Analog (A2) Assembly.
c. Remove the screw located near the center of the AC Convertor Assembly.
d. Remove the AC Convertor Assembly.
e. T o replace the AC Convertor Assembly, reverse steps a through d.
6-31. Analog (A2) Assembly Removal
6-32. The Rear Tern~inal Assembly or Plug-In Assembly, Top Cover, Plug-In Support Assembly, and AC
Convertor (A3) Assembly must be removed prior t o removing the Analog (A2) Assembly. Remove the
Analog Assembly as follows:
a. Remove the Rear Terminal Assembly (paragraph 6-17) or Plug-In Assembly (paragraph 6-19), T o p
Cover (paragraph 6-21), Plug-In Support Assembly (paragraph 6-27) and AC Convertor Assembly
(paragraph 6-29).
b. Disconnect the five input wires from the front panel and connectors AI-P502 and A2-P901.