Potomac Instruments FIM-21 - Page 23

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SECTION 4. MAJNTENANCE (Cont.)
Lamp Replacement (Cont.)
(Meter Lamp) Fil1-21, Serial Numbers. 123 and higher.
FJM-41, All
a . Stand the FIM upright on a flat surface, with the cover
open. Set switches as follows:
FUNCTION to OFF
LIGHTS to OFF
b. Remove the four socket-head screws directly above and
below the meter, which fasten the meter panel to the
front panel. Ease out the meter and panel and rest
the met er fa ce- down on a small block or other support.
c. The lamps should appear projecting from the main panel
below the meter hole. Pull the bad lamp out far enough
to grip the socket and pull it out of the socket. Be
sure that the socket does not pull back inside t he FIM:
when released.
d. Remove the rubber gronunet or washer from the old lamp
and slip it onto the new one from the back, pushing it
up against the shoulder of the lamp.
e. Insert the new lamp in its socket and push the lamp
into approximately the original position of the old
lamp.
f. Repeat steps c-e for the other lamp if necessary.
g. Re place the meter and panel in the main panel, being
ce~tain tha t t~e lamps are properly seated in the
met er and that the meter panel seats snugly against
the main panel. Replace the four screws.
h. Check the new lamps for proper operation by switching
the FUNCTION switch to BATT and the LIGHT switch on
(red spot showing).
To Remove FIM from Case
l .
Place upright on bench with the cover open. Tune to
540 KHz, remove the four screws retaining the spring
arms, and slip off the spring arms (1/8
11
Allen wrench).
2. With the cover closed, remove the 12 screws holding the
case to the front panel (5/64
11
Allen wrench).
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