I built this amplifier circuit and it works but I have some questions.
Component values are as follows:
R1 = 100 K ohm; R2 = 15K ohm; R3 = 1K ohm; R4 = 100 ohm
C1 = 1 uF; C2 = 1000 uF
D1 = D2 = 1N4148
Q1 = 2N3904; Q2 = TIP31C; Q3 = TIP32C
Supply Voltage = 12 V
Load = 8 ohm speaker
DC Readings:
VCQ1 = 6.90V; VBQ1 = 1.10V; VEQ1 = 0.40V; VCEQ1 = 6.57V
VCQ2 = 11.94V; VBQ2 = 8.11V; VEQ2 = 7.50V; VCEQ2 = 4.48V
VCQ3 = 0.00V; VBQ3 = 6.90V; VEQ3 = 7.50V; VCEQ3 = 7.51V
IcQ1 = 0.11mA; IcQ2 = IcQ3 = 6.75mA
Questions:
1) Should VEQ2 = VEQ3 not be 6.00 Volts?
2) According to my calculations, I expected VCQ1 = 5.30V, VBQ1 = 1.60V
and VEQ1 = 0.90V. I checked the resistor values and they are pretty
close to what they should be. I must be missing something.
Thanks in advance for any comments.
Component values are as follows:
R1 = 100 K ohm; R2 = 15K ohm; R3 = 1K ohm; R4 = 100 ohm
C1 = 1 uF; C2 = 1000 uF
D1 = D2 = 1N4148
Q1 = 2N3904; Q2 = TIP31C; Q3 = TIP32C
Supply Voltage = 12 V
Load = 8 ohm speaker
DC Readings:
VCQ1 = 6.90V; VBQ1 = 1.10V; VEQ1 = 0.40V; VCEQ1 = 6.57V
VCQ2 = 11.94V; VBQ2 = 8.11V; VEQ2 = 7.50V; VCEQ2 = 4.48V
VCQ3 = 0.00V; VBQ3 = 6.90V; VEQ3 = 7.50V; VCEQ3 = 7.51V
IcQ1 = 0.11mA; IcQ2 = IcQ3 = 6.75mA
Questions:
1) Should VEQ2 = VEQ3 not be 6.00 Volts?
2) According to my calculations, I expected VCQ1 = 5.30V, VBQ1 = 1.60V
and VEQ1 = 0.90V. I checked the resistor values and they are pretty
close to what they should be. I must be missing something.
Thanks in advance for any comments.
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