Re: How transmitters work.
Impedance mismatch will mean that the antenna will not radiate 260mW, a
significant amount will be reflected back to the op-amp. That is why the
traditional approach exists.
"BobG" <bobgardner@xxxxxxx> wrote in message
news:1114052307.475407.266430@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
> While we're talking about transmitters, let me ask this question: Lets
> say I have a video opamp that will put out +-10V at 1 MHz into 377
> ohms... can I hook this to an antenna? P=E^2/R=100/377= 260mw In
> other words, the 'traditional' approach of making everything 50 ohms
> and using tuned class c amps is just how it was done with tubes in the
> 40s right? If the impedance of the antenna is 377 ohms, and I can drive
> it direct, thats all it takes, right?
>
.
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(uk.radio.amateur) |
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