Martin wrote:

> Let me preface by saying that I'm not an RF guy..
> How could the SWR fold-back protection drop the power more-so than a
> high SWR antenna? Does it see some amount of reflected power and then
> cut down the power until it sees some arbitrarily acceptable level of
> reflection?

***  I posted this yesterday, but it didn't show.  Hopefully it will work 
this time.


 That's pretty much it.  Having a high SWR doesn't automatically mean that 
the antenna is an inefficient radiator, there is no corelation.
 IOW, a high SWR doesn't necessarily make the radiated power less, folding 
back sure does though.  You can have a perfectly resonant antenna and still 
have a "high" SWR just because of the type of antenna.  For example a 
standard dipole is roughly 75 Ohms at the feedpoint.  A folded dipole or 
full-wave loop can approach 300 Ohms at resonance.  Given the typical 
transmitter output of 50 Ohms, you can see the problem. 

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