Chapter 7
Theory of Operations
7.1 Troubleshooting
The following paragraphs give basic procedures for troubleshooting and component
replacement in the 2105.
7.1.1 Component Replacement
The 2105 accuracy and reliability can only be maintained if the following precautions are taken
when changing a component:
•
Remove all power from the instrument and input terminals before attempting
component replacement.
•
Use only the specified component or its exact equivalent. Spare parts may be ordered
from your nearest Valhalla Scientific Service Center by referring to the Valhalla part
number listed in the Parts List section at the back of this manual. Please provide the
type and serial number of the instrument with your order.
•
Use only 63/37 rosin core electronic grade solder with a 50W (or lower) maximum
power soldering iron.
•
Many of the semiconductor devices used in the 2105 can be damaged by static
discharges. Thus, the user should follow strict static-free procedures to ensure that
damage does not occur.
•
When re-soldering components the user must ensure that the highest possible quality
soldering is used. A dry joint may cause the 2105 to drift outside of its specification
limits.
•
Minimize handling of components and assemblies. Transport and store components in
their original containers.
•
Discharge static build-up on the user and instrument prior to handling components or
assemblies.
•
Handle the components such that all (or as many as possible) of the leads are in contact
with the user.
•
Never slide a component over a surface.
•
Use a grounded tip soldering iron and ensure that the assembly being (de)soldered is
also grounded.
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