Difference between "power amplifier" and "aud

Hello there,

I'm quite confuse with these 2 amplifiers, an audio amplifier amplifies the signal, a power amplifier amplifies the power. But what difference does they made?

What about VHF amplifier?

Since i'm building a FM transmitter, after the modulation of the FM signal, what kind of amplifier should i choose [VHF amp, power amp], before i sent the modulated signal into my antenna. I know it's not audio amp, no use amplifing the amplitude... :p

again, thanks in advance

Alex
oasis4355@yahoo.com

an amplifer is an amplifier is an amplifier...

the terms you describe are more or less informal

If you tell me an audio amplifier, i think an amplifier that works around 20Hz to 20 kHz. If you say VHF amplifier, I think 30MHz to 300 MHz since that is the definition of VHF. If you say power amplifier, I think > 1watt.

For your project, I think a 1 watt VHF class C RF amplifier is what you need.

You asked about an audio amplifer IC earlier. You would not use this between your transmitter and antenna. It won't work at this high a frequency (100MHz).

Thanks,

actually about the audio IC, i was planning to use it at the Reciever.

about the class-c amplifier you mentioned earlier, what's the function of C2 (variable capacitor)?


For the VHF amplifier, i wonder if i can use this amplifier instead?

http://www.electronics-lab.com/projects/rf/009/

Alex