Eico 950B - Control Knob Alignment; Initial Power-Up and Calibration; Cabinet Assembly

4) Align the contro! knobs as follows:
a) Fastena knob to the POWER FACTOR control. First turn it clockwise to ensure that it is in the "AC ON" position,
and then turn it counter-clockwise until the "AC OFF" position is "felt". Do_not turn tothe "AC“OFF" position. Loosen the
knob set screw, line the knob up with the "©" position on the power factor dial, and retighten the set screw.
b) Fasten a knob to the RANGE switch and turn It to the extreme counter-clockwise position. Loosen the knob set
screw, line up the knob with the "10 mmf - 5000 mmf" position on the range dial, and retighten the set screw. (The set
screw should tighten against the "flat" on the switch shaft. If it does not, loosen the nut securing the switch and adjust
the switch until the "flat" is in the required position.) .
c) Fasten a knob on the "VOLTAGE potentiometer and turn it to the extreme clockwise position. Loosen the knob
set screw, line the knob up with the 500 position on the voltage dial, and retighten the set screw.
5) Connect an ohmmeter from B plus (V17~8) to ground; the resistance should not be less than 50,000 ohms nor should it
vary as the RANGEswitch is rotated. Then connect the ohmmefer from B minus (V173 or 5) to ground; the resistance should
not be less than 60,000 ohms nor should it vary as the range switch is rotated. If any of the above conditions do not
obtain, recheck the circuit (B plus or B minus as required). De not apply power until the trouble is remedied.
6) Insert the line cord and turn the instrument on by rotating the AC switch on the POWER FACTOR potentiometer clock=
wise. The filaments should light immediately. If not, turn the instrument off and check the filament circuit. Do not
leave the power on as this could damage the power transformer. The magic eye tube should show a green glow within |
minute. If not, recheck the B plus circuit.
7) CALIBRATION: Turn the instrument on and allow a few minutes for warm-up. Set the RANGE switch at the "5 KQ =
5 MQ" position, and connect the 200 KQ (.2 MQ) precision calibrating resistor provided across the "CAP.-RES. TEST" bind-
ing posts. Fasten the pointer indicator knob to the shaft of the center potentiometer. Rotate the center potentiometer
until the eye shows maximum opening (bridge balance). Loosen the knob set screw, set the pointer at .2M on the dial,
and retighten the set screw. Check to determine whether or not any shaft movement has occurred during the knobresetting
process. If the eye shows maximum opening with the pointer set at .2M on the dial, no shaft movement has occurred and
the calibration is completed. Remove the 200 KQ precision resistor and store it for reference.
8) Install the rubber feet in the openings provided inthe bottom of the cabinet as shown. The method is to work the rounded
portion of each foot into interior of the cabinet from the outside, using a small screw driver. The flat portion should be
the actual resting or contact surface.
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9) Mount the handle on the cabinet with 2 10-24 screws as shown in Fig. 9.
10) Run the ac line cord through the rear cabinet opening and insert the completed unit in the cabinet. Align the hole
in the cabinet rear and the rear chassis apron and insert 1 #6 P.K. screw. Then align the 8 panel holes with the corre=
sponding holes in the cabinet flange and insert 8 #6 P.K. screws. Tighten all screws.
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