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Old March 13th 05, 11:18 PM
 
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thanks again for the help...your answers led me to a couple other
questions, if i may ask?

xpyttl wrote:

In amateur practice, the impedance of almost anything that connects

together
at RF is 50 ohms or converted to 50 ohms. Given that, the power

level then
converts directly to voltage and current.


so if i were to design a transmitter around an COTS amp, how would i
determine what i needed to "drive" it at, in terms of voltage? if i
have 3 variables (V, I, and R) then i'd need to know 2 of the 3, then i
can solve for the third... as it is, i only know R...?

This is one of the reasons that FM signals have so much higher

quality ...
any noise is actually a result of noise in the receiver (or

transmitter)
rather than the atmosphere. With other modes, not only can you hear

the
atmospheric noise, but at lower frequencies, the atmospheric noise is

many
times higher than the noise inherent in the receiver.


so i imagine people can do CW over FM, but does it usually occur on (I
guess what would be called) a simplified AM transceiver? either a
signal's present or not?

also, when people refer to ASK and FSK, is ASK basically an audio
output that's been sent over FM? and FSK is more like CW, only to a
receiver that can monitor both mark and space (0 and 1) frequencies?

thanks again!
jason