5
3 SETTING THE FREQUENCY
Using the WHEEL button on the chopper controller, set the wheel type to match the frequency
range desired. To change the wheel type, push the Wheel button until the LED lights under the
desired wheel type.
Wheel Type 2 = 4 Hz to 213 Hz
Wheel Type 60 = 120 Hz to 2.00 kHz
Using the Sync button, select the source to be internal. To change the Sync source, push the
Sync button until the INT LED lights.
Select the Mode to be NORMAL. To change the Mode selection, press the Mode button until
the NORMAL LED lights.
Press the Set button until the FREQ LED is lit. The internal synthesizer frequency may be set to
three significant digits. The significant digit to be modified may be selected by the left and right
arrow keys. The magnitude of the digit may be changed with the up and down arrow keys. If the
display overflows or underflows, the display will change between the Hz/kHz LEDs and move
the decimal point to maintain three significant digits of resolution.
Press the Measure button until the SYNC IN LED is lit. This displays the chopping frequency.
NOTE: Do not take any measurements until the chopper controller has locked in on the
desired frequency.
The red UNLCK LED indicates when the Chopper is not synchronized to an internal or external
sync frequency. In addition, the UNLCK LED will blink when an external sync frequency
exceeds the limits for a particular wheel.
4 SAVING AND RECALLING THE SETUP
To save the setting, press the Set button until the STORE LED lights. Use the up and down
arrow keys to assign the instrument setup number, 1-9. Press the left or right arrow key to save
the settings under the setup number. If the setup is not saved, upon powering up the chopper
controller, it will revert to its last operating parameters before it was shut down.
To recall an instrument setup, press the Set button until the RECALL LED lights. The up and
down arrow keys are used to select the instrument setup number, again, ranging from 0 to 9.
Press the left or right arrow key to recall the displayed instrument setup. The display will blink
when the recall process is complete.
To restore the chopper controller to its default factory settings, recall setup 0.
