A schematic is attached for a C`E Voltage Amplifier Circuit.

 

And the question is ?

 

Schematic is for a CE Voltage Amplifier Circuit.

According to Heath-Zenith, this circuit was designed for a centered Q-point.

Component values are: R1 = 3.9K Ω, R2 = 1.5KΩ, Rc = 3.3KΩ, Re1 = 120Ω, RE2 = 1.5kΩ,
C1 = C2 = C3 = 47uF, Transistor = 2N3904.

Supply voltage = 20V
Gain = 10
Icq = 3 mA

Measured voltages are: Vc = 10.3V, Ve = 4.8V, Vb = 5.5V, Vceq = 5.4V.

What would the maximum, undistorted ouput voltage be? Heath claims that it should be 4.42V.

Thanks

 

View attachment 119321 A schematic is attached for a C`E Voltage Amplifier Circuit.

50 years ago that would have been a good question.

 

According to Heath-Zenith

Who ??

his circuit was designed for a centered Q-point.
Component values are: R1 = 3.9K Ω, R2 = 1.5KΩ, Rc = 3.3KΩ, Re1 = 120Ω, RE2 = 1.5kΩ,
C1 = C2 = C3 = 47uF, Transistor = 2N3904.
Supply voltage = 20V
Gain = 10
Icq = 3 mA
Measured voltages are: Vc = 10.3V, Ve = 4.8V, Vb = 5.5V, Vceq = 5.4V.

R1 and R2 have a strange low values but ok.

What would the maximum, undistorted ouput voltage be? Heath claims that it should be 4.42V.

Without the load resistance (RL) the minimum voltage at collector will be equal around 5.2V

Vc_min ≈ Ve+Vce(sat) ≈ 4.8V+0.2V ≈ 5V ---> so the voltage at Vc can swing from 10.3V down to 5V----> 10.3V - 5V ≈ 5.3Vpeak = 3.74V RMS.

https://leachlegacy.ece.gatech.edu/ece3050/notes/bjt/bjtclipsu08.pdf

 

Jony130 wrote:
Who?

Zenith, a consumer electronics company bought the struggling electronic kit maker Heath (as in Heath Kits) and went out of business soon after that.

 

What would the maximum, undistorted ouput voltage be? Heath claims that it should be 4.42V.

I calculate around 5V (10V peak to peak); approximate voltages for Vc and Ve, 10V and 5V, respectively.

 

Referring to this Heath-Zenith course material that I have (I question it's quality). It
says that this circuit will have an output that rides on a Vc of 10.3 V. So that the max
undistorted output would be 10.3 + 4.4 = 14.7V peak and a minimum undistorted output
of 10.3-4.4 = 5.9V peak.

This is so confusing.

Regards,
John

 

Referring to this Heath-Zenith course material that I have (I question it's quality). It
says that this circuit will have an output that rides on a Vc of 10.3 V. So that the max
undistorted output would be 10.3 + 4.4 = 14.7V peak and a minimum undistorted output
of 10.3-4.4 = 5.9V peak.

This is so confusing.

Regards,
John

Did you know that candles have been replaced by light bulbs, or are still using them!!

 

Jony130 wrote:
Who?

Zenith, a consumer electronics company bought the struggling electronic kit maker Heath (as in Heath Kits) and went out of business soon after that.

Why do you allow ignorant jerks like Dodgydave to remain members of this site. People are trying to learn and we appreciate
those that help us! We don't need the ignorance that some of these people are displaying!

 

Why do you allow ignorant jerks like Dodgydave and Jony130 remain members of this site. People are trying to learn and we appreciate
those that help us! We don't need the ignorance that some of these people are displaying!

If you do not watch your language and curb your temper you will be booted of this site pronto.

 

It
says that this circuit will have an output that rides on a Vc of 10.3 V. So that the max
undistorted output would be 10.3 + 4.4 = 14.7V peak and a minimum undistorted output
of 10.3-4.4 = 5.9V peak.

This is so confusing.

This is what I calculated:

The output signal will be distorted when the positive portion approaches 20V or the negative portion causes the transistor to begin saturating.

 

If you do not watch your language and not curb your temper you will be booted of this site pronto.

 

No. You ban the jerks!

 

This is what I calculated:
View attachment 119328View attachment 119329
The output signal will be distorted when the positive portion approaches 20V or the negative portion causes the transistor to begin saturating.

Thanks Dennis.

 

We don't need

While I agree with your sentiments, your attitude is a bit thick for someone with only 4 messages. I recommend that you focus on the responses that help, and ignore the ignorables. Basic transistor circuit theory never goes out of style, but an over-exaggerated view of one's place in the universe never is helpful.

ak

 

If you do not watch your language and curb your temper you will be booted of this site pronto.

Just because some people are long-time members, doesn't mean their behavior is appropriate/friendly.

 

No. You ban the jerks!

john55 was permanently banned yesterday. You are headed for the same fate.

 

Offensive posts have been removed from public view.
OP permanently banned.
Thread is now closed.