Circuit Lab.
Experiment-3
Operating the function
generator and digital
oscilloscope
Quiz
• A(t)=5.sin(100pt)
–Draw the graphic of A(t) signal
–Calculate amplitude, frequency
and time period.
FUNCTION GENERATOR
GW INSTEK SFG-2120
-Generation of Test Signals
-Square Wave
-Sine Wave
-Triangular Wave
-Digitally Controlled Frequency (0.1 Hz ... 20 MHz)
-Manually Controlled Amplitude (0...10V (pp))
-50 ohm BNC output
-TTL/CMOS BNC output
-Counter BNC input for frequency counter
-Amplitude, Frequency Modulation, Variable Mod. index
FUNCTION GENERATOR
GW INSTEK SFG-2120
FUNCTION GENERATOR
GW INSTEK SFG-2120
How can we see the signal?
• Oscilloscope
GW Instek GDS 1102
 100 MHz
 2 channels
 1 M ohm input impedance
 FFT, A*B, A+B, A-B
 Digital Measurements (Vpp, Vdc, Frequency...)
 Saving Graphical Data (SD Card Interface)
DIGITAL OSCILLOSCOPE
GW Instek GDS-1102
Connection
• BNC Connectors (RF Connector)
(British Naval Connector)
Cable
• RG-58/U Coaxial Cable
• Low-power signal and RF connections
• Characteristic impedance: 50 ohm
A: outer plastic sheath
B: woven copper shield
C: inner dielectric insulator
D: copper core
Oscilloscope Probe
Equivalent Circuits
1x Probe
R1=1M ohm
C1=1-10 pF
10x Probe
R1=9M ohm
C1=1-10pF
Oscilloscope
Input
R2=1M ohm
C2=20 pF
Osilloscope Probe Test
• Check the probe set : 1x or 10x
• Connect the BNC connector of the Oscilloscope
Probe to CH1
• Connect the test connector of the oscilloscope
probe to Test Output
• Press Run/Stop Key
• Measure the frequency and the amplitude of the
test signal
Osilloscope Probe Compensation
Volt
Division
of CH1
Volt
Division
of CH2
Time
Division
1st Job:
• A(t)=5.sin(100pt)
– Amplitude?
• peak (p)
• peak-to-peak (pp)
– Time period? (seconds)
– Frequency? (Hertz)
2nd Job
• Derive the sine signal using
function generator and oscilloscope
3rd Job
• Generate
–4 V (p-p)
–10 kHz
–Square Wave
4th Job
• Generate
–100 mV (p-p)
–1 kHz
–Sine Wave
Cursors