[Towertalk] Efficiency of antennas

[Pete Smith]

I've seen some fairly interesting claims recently for the efficiency of 
yagis with coil loading.  I'm not quite sure what efficiency means in this 
context -- is it simply the percentage of the driving power that is 
actually available to be coupled to what we used to call the ether?  If so, 
is it just another way of expressing the amount of loss in loading 
coils?  If an antenna manufacturer claims 90 percent efficiency, is that 
just another way of saying that 1/10 of the applied power is being 
dissipated in heat?

73, Pete N4ZR