B&K Precision 1796 - Manual - Manual (Page 17)

your area. Before you purchase check the electrical parts list for the proper value
rating, tolerance and description.
5.5.2 ORDERING PROCEDURE : When ordering replacement parts from B+K Inc.
please include the following minimum information :
1. Power Supply Type ( 1791 B & K ), Model Code : 350
2. Power Supply Serial Number ( For example, 01040036 )
3. A description of the part ( if electrical include the circuit number ).
5.5.3 CIRCUIT BOARDS : If a circuit board is damaged beyond repair, the entire
assembly including all soldered-on components can be replaced. To remove or
replace a board, proceed as follows :-
1. Disconnect all Sockets & leads connected to the board ( both soldered
lead connections and solderless pin connections ).
2. Remove all mounting screws holding the board in the instrument. Rmove
any knobs, etc. that would prevent the board from being lifted out of the
instrument.
3. Lift the circuit board out of the unit. Do not force or bend the board.
4. To replace the board, reverse the order of removal. Use care when
replacing pin connectors. If forced into place incorrectly positioned, the
pin connectors may be damaged.
5.5.4 TRANSISTORS AND IC's : Transistors and IC's should not be replaced unless
they are actually defective. If removed from their sockets during routing
maintenance, return them to their original sockets. Unnecessary replacement or
switching of semiconductor devices may affect the calibration of the instruments.
When a transistor is replaced, check the operation of the part of the instrument
that may be affected.
Replacement semiconductors should be of the original type or a direct
replacement. When removing soldered-in transistors, use an approved anti-static
suction-type desoldering tool to remove the solder from the holes in the circuit
board.
An extracting tool should be used to remove the 14 pin integrated circuits to
prevent damage to the pins. If an extracting the pins. Pull slowly and evenly on
both ends of the IC. Avoid having one end of the IC disengage from the socket
before the other end.
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