Remove the shorting plug from the amplifier
circuitboard connection BC3 (fig. 4-1).
Set the VOM to
the RX100 range and connect the VOM leads to the meter
studs (+ to + and - to -).
The meter should deflect full
scale and the VOM should indicate approximately 40 ohms.
Disconnect one lead and the meter should return smoothly
If the meter is open (infinite resistance and
does not deflect) or appears to stick at any point while
returning to zero,
it should be replaced.
Circuit boards check.
Replace shorting plug. Rig meter
for battery operation.
Install the battery pack cable on
the BC and connect.
The spectrophotometer circuit boards
can be checked bytaking voltage measurements at various
If the proper readings are not obtained, the
applicable circuit board should be replaced.
Most of the
checks can be made with the instrument operating on
This practice is recommended as a safety