Checkline DT-900 - Manual (Page 8)

8
4.0 T ACHOMETER M ODE
When in the Tachometer Mode the strobe will not flash but can be used like a hand-
held tachometer. The DT-900 will display the frequency of the signal source connected
to it. To use the Tachometer Mode:
1. Turn on the strobe and press the Mode Control button until TachMode appears
on the display.
2. Connect a signal source to the external signal connector (See page 3)
using a stereo type phono connector (see page 5).
3. If a valid signal source is detected, the DT-900 stroboscope LCD will display
the signal rate and the LED will be green.
4. If no valid signal source is detected, the strobe will display TachMode – no
input and the LED will be red.
5. When using the Tachometer Mode, the maximum signal rate is 59,000 FPM
and the minimum signal rate is 40 FPM.
6. To exit the Tachometer Mode and return to normal strobe operation, disconnect
the signal source and press the Mode Control button once to enter the Internal
Triggering Mode.
9
5.0 F LASH T UBE REPLACEMENT
When an FPM reading is displayed, but the strobe is not flashing, the flash tube may
need to be replaced.
WARNING: The surface of the DT-900 stroboscope lens especially the bulb
can get hot during continued use. Caution should be taken to allow sufficient
cooling time before attempting to replace the bulb.
WARNING: The DT-900 stroboscope operates at High Voltage inside the
lamp and the electronic compartment. Please disconnect prior to lamp
replacement.
Protective Lens
Insert screwdriver
into opening
1. Remove the front lens from the strobe by inserting the
tip of a screwdriver into one of the vent holes. Gently
pry the lens out (Be careful not to damage the edge
of the lens.). Pry each side out, one by one until the
lens can be removed.
NOTE: The reflector does not need to be removed to
replace the bulb. It should remain in place.
2. Protect the bulb from any oil or residue by using a piece of cloth between your
fingers and the bulb. Grasp and pull the bulb to remove it.
3. Handle the new bulb with a piece of cloth. Insert the new bulb in the connector by
pressing it in place.
IMPORTANT: Be sure to orient the red dot on the bulb connector with the
red dot on the strobe connector. If the bulb is inserted backwards, it
will fail to operate as specified.