Instruction manual

SI-H Muscle Testers

WORLD PRECISION IN STRU MENTS

Fig. 22 (Left) This pulser assembly has no force transducer mounted in it.

Fig. 23 (Right) A force transducer is mounted in the SI-AOSUB pulser assembly.

Keep in mind that:

• The closer the anti-oscillation frequency matches the resonance frequency of the

force transducer, the more the ringing phenomenon is removed from the force

signal.

• The resonance frequency can be evoked at anti-oscillation frequencies that are

multiples of the resonance frequency. For example, if the resonance frequency

of the transducer is 200Hz, it can also be evoked when the anti-oscillation

frequency is set to 400 or 600Hz. The anti-oscillation ﬁ lter works best when

the anti-oscillation frequency is set at the actual resonance frequency of the

transducer.

1. Slide the force transducer, with its tissue mount in position, forward into the pulser

( magnetic driver assembly) until it rests against the stop at the front of the pulser. See

Fig. 23.

2. Attach the cable of the pulser to BNC connector of the Pulser Output on the front of

the Anti-Oscillation module (SI-AOSUB).

3. Using the potentiometer adjustment tool provided with the signal conditioning

ampliﬁ er system, rotate the calibration screw of the Anti-oscillation Frequency

Adjustment potentiometer completely to the left (counter-clockwise). The anti-

oscillation frequency is now set to the lowest possible level.

4. Turn the Pulser Amplitude Adjustment knob completely to the left (counter-clock-

wise). The amplitude of the anti-oscillation frequency is now set to the lowest pos-

sible level. Then, slowly turn the Pulse Amplitude Adjustment knob to the right until

a couple of bars on the Signal Amplitude LED array are illuminated.

5. Using the potentiometer adjustment tool, slowly turn the calibration screw of the

Anti-oscillation Frequency Adjustment potentiometer to the right (clockwise) while

observing the Signal Amplitude LED array. As the calibration screw is turned to the

right, the anti-oscillation frequency gets closer to the resonance frequency of the

transducer, and the transducer begins to oscillate at higher amplitude as indicated by

the increased number of lights in the LED array that illuminate.