Help with analog circuit design

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ANDONG

Joined Dec 5, 2023
2
Design an audio signal amplification circuit using a triode.It is required to amplify the signal without distortion:

1. the signal source voltage is 10mV and the signal source internal resistance RS = 500Ω;

2. Amplification 1000 times;

3. Load resistance RL = 8Ω
 

Ian0

Joined Aug 7, 2020
9,531
Design an audio signal amplification circuit using a triode.It is required to amplify the signal without distortion:

1. the signal source voltage is 10mV and the signal source internal resistance RS = 500Ω;

2. Amplification 1000 times;

3. Load resistance RL = 8Ω
The absolute maximum gain you will get from a triode valve is the value of μ.
There are no triodes with μ>125.
You would struggle to get a gain of 1000 from a pentode.
No triode can drive an 8Ω load. You would need a transformer.
Read Merlin Blencowe's book if you are interested in valve design.
https://www.waterstones.com/author/merlin-blencowe/1076386
 

WBahn

Joined Mar 31, 2012
29,885
Design an audio signal amplification circuit using a triode.It is required to amplify the signal without distortion:

1. the signal source voltage is 10mV and the signal source internal resistance RS = 500Ω;

2. Amplification 1000 times;

3. Load resistance RL = 8Ω
Where are these requirements coming from?

What does it mean "without distortion"?

There WILL be distortion, you need a spec on how much distortion is acceptable (which included indicating what kind of distortion).
 

Papabravo

Joined Feb 24, 2006
21,029
This is homework help, not homework done for you. You need to show your best efforts at developing a solution. A good start would be telling us what you already know.
 

BobTPH

Joined Jun 5, 2013
8,686
The absolute maximum gain you will get from a triode valve is the value of μ.
There are no triodes with μ>125.
A regenerative RF circuit can attain ridiculously high gain with a single triode or transistor.

But certainly not with no distortion.
 

Ian0

Joined Aug 7, 2020
9,531
A regenerative RF circuit can attain ridiculously high gain with a single triode or transistor.

But certainly not with no distortion.
I learned transistors first, and valves later out of curiosity “what are these weird high-voltage JFETs in glass tubes all about?”.
I have heard of regenerative circuits, but the TS did say “audio”, and regeneration (usually from microphones) in audio is not usually a good thing!
 
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