To eliminate unwanted noise signal of measurement, it is often necessary to continue the use of the circuit or eliminate the signals in a specific frequency region. The circuit is called a filter. A simple filter can be made of a resistor and a capacitor. This circuit could form the filter circuit Lowpass and Highpass filter.
Filter Lowpass
Lowpass can eliminate high-frequency and low-frequency signals continue. In this case the amplitude value whose value was fixed at a specific frequency or made reducing to zero at certain frequencies. With Lowpass filter, if there is a signal with a frequency higher Highpass, the amplitude of the signal will decrease. This circuit can be made as shown in Figure 2:26 (a). The experimental results using the oscilloscope measurement tool shown in Figure 2.27.
Figure 2.27 Experimental Results of Passive filter circuit
By providing different frequency value between signal V in in Figure 2.27 (a) and V in, Figure 2.27 (b) then generates a signal V out different in terms of amplitude. But the value of the frequency unchanged. And no phase shift between V in and V out, it’s just a question of changing phase are not discussed in this book. In contrast to the Highpass filter, F ilter is able to eliminate low-frequency signals and high-frequency forward. Surely amplitude becomes small or fixed.
Pictures 2:28 Experimental Results of Passive filter circuit
RC circuit for this filter is shown in Figure 2:26 (b). The experimental results using the oscilloscope measurement tool shown in Fig 2:28. By providing value between signals of different frequencies in V in Figure 2:28 (a) and V in, Figure 2:28 (b) then generates a signal V out different in terms of amplitude. But the value of the frequency unchanged.
Figure 2.29 Model of Measurement and Signal Conditioning
In this section we discussed about designing user, something that must be considered when designing an analog signal conditioning system. Example here shows how these instructions are used to develop a design. The instructions below to ensure that any problems could be dipahai properly and discussed herein regarding matters that are important. Not all leads will be important in designing any, may be incompatible with some applications that we make.
In many cases, not enough information was lacking in indicates a problem with either, then a designer must have good technical ability danterlatih in every part of the design. Figure 2.29 shows a model of measurement and signal conditioner. In some cases the entire system was developed, from the selection of sensors to design the signal conditioner. In others, only signal conditioners to be developed. Made general instructions below. Because the sensor is chosen from those available, made the actual design and completely appropriate to the signal conditioner.