Figure 3.1 Stages in electrical signal measuring system.

Figure 3.2 Generic voltage amplifier.

Figure 3.3 Amplifier frequency response.

Figure 3.4 Frequency distortion of a square wave due to high-frequency attenuation.

Figure 3.5 Effect of phase angle on signal.

Figure 3.6 Typical phase-angle response of amplifier.

Figure 3.7 Effect on signal of linear and nonlinear phase-angle variation with frequency: (a) original signal; (b) phase angle varies linearly with frequency; (c) phase angle varies nonlinearly with frequency.

Figure 3. 8 Models for (a) source and (b) amplifier Figure 3.8 Models for (a) source and (b) amplifier. (Based on Franco, 2002.)

Figure 3.9 Combined model of (a) input source, (b) amplifier, and (c) output load. (Based on Franco, 2002.)

Figure E3.1

Figure 3.10 Operational amplifier symbol and simplified model.

Figure 3.11 Simple noninverting amplifier using an op-amp.

Figure 3.12 Frequency response of op-amp amplifier.

Figure 3.13 Inverting op-amp amplifier.

Figure 3. 14 True differential input instrument amplifier Figure 3.14 True differential input instrument amplifier. (From Franco, 2002.)

Figure 3.15 Attenuation using dividing network.

Figure E3.3a

Figure E3.3b

Figure 3.16 Categories of electrical filters: (a) lowpass; (b) highpass; (c) bandpass; (d) bandstop.

Figure 3.17 Gain of lowpass Butterworth filters as a function of order and frequency.

Figure 3.18 Gain of lowpass Chebyshev filters as a function of order and frequency.

Figure 3.19 Comparison of Butterworth and Bessel phase-angle variation with frequency.

Figure 3.20 Gain of lowpass Bessel filters as a function of order and frequency.

Figure 3.21 Lowpass Butterworth filter using op-amp: (a) op-amp circuit; (b) frequency response.

Figure 3.22 First-order Butterworth highpass filter using an op-amp: (a) op-amp circuit; (b) frequency response.

Figure 3.23 Bandpass filter using op-amp: (a) op-amp circuit; (b) frequency response.

Figure 3.24 Op-amp circuits for (a) integration and (b) differentiation.

Figure 3.25 Op-amp comparator: (a) circuit; (b) output voltage.

Figure 3.26 Digital multimeter with a digital voltmeter as a mode of operation. (Courtesy of Triplett Corp.)

Figure 3.27 Cathode ray oscilloscope. (Courtesy of Tektronix, Inc.)

Figure 3.28 Schematic view of cathode ray tube.

Figure 3.29 Block diagram of analog oscilloscope.

Figure 3.30 Strip-chart recorder.

Figure 3.31 Interference sources for signal wiring.

Figure 3.32 Source of ground loop.

Figure 3.33 Grounding and shielding of system components.

Figure 3.34 Current-loop signal transmission.