Tektronix 1705A, Instruction Manual

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1705A Spectrum Monitor
6- 1
Section 6
Maintenance
This section contains instructions for preventive maintenance, diagnostics,
general troubleshooting, and corrective maintenance. If the instrument does not
function properly, troubleshooting and corrective measures should be taken
immediately to circumvent additional problems.
PREVENTIVE MAINTENANCE
Preventive maintenance consists of cleaning, visual inspection, performance
checking, and, if needed, readjustment. The preventive maintenance schedule
established for the instrument should be based on the environment in which it is
operated and the amount of use. Under average conditions, scheduled preventive
maintenance should be performed every 2000 hours of operation.
CAUTION.
A 2% RMA flux content solder is recommended for making repairs in
this instrument. Cleaning of rosin residue is not recommended. Most cleaning
solvents tend to reactivate the rosin and spread it under components where it
may cause corrosion under humid conditions. The rosin residue, if left alone,
does not exhibit these corrosive properties.
The instrument should be cleaned often enough to prevent dust or dirt from
accumulating. Dirt acts as a thermal insulating blanket that prevents effective
heat dissipation, and can provide high-resistance electrical leakage paths between
conductors or components in a humid environment.
Exterior . Clean the dust from the outside of the instrument by wiping with a
soft cloth or small brush. A brush is especially useful to remove dust from
around the selector buttons, knobs, and connectors. Hardened dirt may be
removed with a cloth dampened in water that contains a mild detergent.
Abrasive cleaners should not be used.
Crt
. Clean the crt protective shield, light filter, and crt face with a soft, lint-free
cloth dampened in denatured alcohol.
Interior . Clean the interior of the instrument by loosening the accumulated dust
with a dry, soft brush. Once the dirt is loosened remove it with low--pressure air
(high-velocity air can damage some parts). Hardened dirt or grease may be
removed with a cotton-tipped applicator dampened with a solution of mild
Cleaning