Hi all,
Using XL = 2pi*f*L and R=XL/Q, I get a little less than 1 ohm of
loss resistance in the traps using the measurements posted here. This
neglects radiation from the trap.
Power loss = I**R and we know R but what is I?
IF we knew the current in the element we could multiply it
by Q (240 in this case) to get the circulating current in the trap. Now
there is a about 4.5 amps at the center of a 50 ohm antenna getting 1000
watts but what is it half way out where the 10m trap is? If the trap were
not there it would be down to .707*I or about 3 amps. But using P=(QI)**2(R)
gives (240*3)**2*1 = 518kW, not too likely.
So what is the current in the element where it connects to the trap?
Anybody got a RF ammeter they can insert in an element?
73, Ed
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Ed Jensen, K5ED, El Paso, TX (ae110@rgfn.epcc.edu)
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