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ME3000 Analog Electronics
Lab 6 - 5/19
3.
Frequency Response
11. Set the function generator output to
40 mVpp.
12. Connect the function generator output to TP1 and reference to GND using the BNC-to-
grabber clips coaxial cable.
13. Connect the oscilloscope CH1 probe to TP1 and GND.
14. Connect the oscilloscope CH2 probe to TP6 and GND.
15. Set the trigger signal to CH1.
16. Sweep the function generator frequency from 2 MHz to 8 MHz in 100 kHz increments.
17. Record the peak-to-peak voltage at the input (CH 1) and output (CH 2), and determine the
magnitude of the voltage gain, A
V
as a function of frequency.
18. Plot the A
V
versus frequency curve and estimate the resonance frequency of the amplifier
from the curve. The input and output waveforms should be approximately 180
out of phase
during resonance. The voltage gain, A
V
is at its maximum when resonance occur, with the
theoretical resonance frequency given as
LC
f
o
2
1
, where L = 4.7
H and C = 100 pF.
19. Use the calculated A
V
at resonance to estimate the value of r
CE
using
m
V
m
V
L
L
ce
L
ce
m
V
g
A
g
A
R
R
r
R
r
g
A
)
||
(
.
20. Calculate the early voltage, V
A
of the transistor using
C
A
ce
I
V
r
.
