AIM: To examine d.c. conditions of a common emitter amplifier.
(a) Connect the circuit as shown in Figure 1. Figure 1
(b) Ask the Supervisor to check the circuit connection.
(c) Copy Table 1 into your answer booklet.
|
VBE(V) |
VEE(V) |
VcE(V) |
Measured |
|
|
|
Calculated |
|
|
|
(d) Measure and record in Table 1 the voltages VBE, VEE and VcE.
(e) Using the following expressions:
(i)VBE = VcE / (R1 + R2) x R2
(ii)VcE =VcE - IcR3;
(iii)VEE = VBE- 0.7 V.
Calculate and record in Table 1:
(i)VBE,
(ii)VEE
(Hi)VcE
[Take
Ic ˜ IE = VEE / R4
(f) Explain briefly, why the two sets of results in Table 1 are different.