- #1
fcukniles
- 26
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Hi, I am doing some revision and i can't remember how to do these, think i might have missed that lecture :-( shame on me, can anyone give me a hand? any help many thanks (the square is ment to be homes)
1. A microphone is delivering an electrical power of 1mW to the input of an amplifier of
gain 36dB. If the output of the amplifier drives a loudspeaker of 3 resistance calculate the speaker voltage and current.
(3.45 V, 1.15 A)
2. A ‘black box’ voltage amplifier has resistive input and output impedances of 10
kilohms and 100 respectively. It has a voltage gain of 1000 when its output is unloaded. Calculate the output voltage if it is fed from a source of 1mV having a resistive source impedance of (i) 0 and (ii) 1k if the amplifier feeds a resistive load of 1k.
(BB Question)
3. The above amplifier is used with a source resistance of 1k.
Measuring between the load terminals and the amplifier input terminals:
(i) What is the loaded voltage gain as a number?
(ii) What is the loaded gain, expressed in dB?
(iii) What is the loaded current gain?
1. A microphone is delivering an electrical power of 1mW to the input of an amplifier of
gain 36dB. If the output of the amplifier drives a loudspeaker of 3 resistance calculate the speaker voltage and current.
(3.45 V, 1.15 A)
2. A ‘black box’ voltage amplifier has resistive input and output impedances of 10
kilohms and 100 respectively. It has a voltage gain of 1000 when its output is unloaded. Calculate the output voltage if it is fed from a source of 1mV having a resistive source impedance of (i) 0 and (ii) 1k if the amplifier feeds a resistive load of 1k.
(BB Question)
3. The above amplifier is used with a source resistance of 1k.
Measuring between the load terminals and the amplifier input terminals:
(i) What is the loaded voltage gain as a number?
(ii) What is the loaded gain, expressed in dB?
(iii) What is the loaded current gain?