Starting the Gaussmeter

1. Turn the ON/OFF switch to ON. The display should now be lit.
2. Verify that the MANU/AUTO switch is down, in the AUTO position.
3. Position the three controls SIGNAL, SWEEP and SYNCHRO at their mid range.
4. Set the probe selection coding wheel to the number of the probe to be used.

Searching the Resonance Signal

Observe the display. The value displayed should slowly vary between the extreme values of the probe's range. The probe is now automatically searching for a resonance signal.

Once the resonance signal is detected, the SIGNAL light is turned on and the value of the magnetic field is displayed.

You can skip the next step and continue with Optimizing the sweep value.

Unsuccessful Signal Search

If the resonance signal is not found, the search goes on until a resonance signal is detected ..: after two full sweep cycles and after having checked that the probe selection dial is set to the number of the probe being used, you should try the following steps to detect the signal:

• Increase the gain of the gaussmeter by turning the SIGNAL control all the way to the right and continue the search for at least one complete cycle.
• Keeping the settings of the SIGNAL and SYNCHRO controls described as under Starting the Gaussmeter, turn the SWEEP control all the way to the left for a zero sweep and continue the signal search for at least one complete cycle. Then, turn the same control all the way to the right for a maximum sweep and wait at least one full cycle again.
• Secure the probe to the center of the magnet gap where the field is probably the most uniform and repeat the measurement with Starting the Gaussmeter .

If nevertheless the resonance signal cannot be found, proceed to Manual Measurement.

Optimizing the Sweep Value

Attach an oscilloscope to the SIGNAL connector. Set the vertical sensitivity of the scope to 5 volts/cm.

Set the TRIGGER switch of the scope to EXTERNAL and connect the external trigger port to the SYNCHRO plug of the gaussmeter. Set the sweep rate of the scope to 2 milliSeconds.

By using the SYNCHRO control of the gaussmeter, bring the resonance signal image to the middle of the oscilloscope screen.

By using the SIGNAL control, set the signal amplitude to 10 volts on the oscilloscope screen.

Adjust the SWEEP control to find a maximum signal value. Then, as above, set this signal to 10 volts.

Optimizing the Position of the Probe

Slowly move the probe inside the gap and search for a position in which the resonance signal reaches a maximum value.

Optimize the SWEEP Value as described in the corresponding chapter. The width of the resonance signal at half its height is in the order of 200 microSeconds corresponding to about 20 microTesla (0.2 Gauss). The period of the SWEEP (back and forth) is 11 milliSeconds. The display provides the average value of the frequencies from 42 resonance pulses (21 sweep periods).