[TenTec] Bazooka antenna

[Steve Hunt]

Folks,

At the risk of stirring up a hornets' nest ......

.... I continue to see claims that the Double Bazooka exhibits a wider 
VSWR bandwidth than the equivalent thickness half-wave dipole. But I 
thought that W2DU had showed conclusively that the "reactance 
cancellation" mechanism claimed for the DB was a fallacy,  and that AI1H 
(ex-W1DTY) had showed that the real explanation for any bandwidth 
increase was losses in the coaxial elements. In other words, the same 
effect as putting a resistor across the feedpoint!

Am I missing something? Is there subsequent work that has proved W2DU 
and AI1H wrong? Or do folks just like using unnecessarily-complex, lossy 
antennas :)

I have an interest in the topic because I just did some related 
experimental and modelling work on using coaxial elements to "shrink" 
the size of a HexBeam. Yes, you get the expected "velocity factor" size 
reduction, but you also get unacceptable losses introduce by the coaxial 
stubs. A HexBeam driver constructed of RG58 would exhibit coax losses of 
about 13dB. If you're interested you can read about it at:

http://www.karinya.net/g3txq/coax_antennas/

I know my test configuration was different from the DB, and that DB 
losses will not be of the same order, but the message is the same: 
"quarter-wave inductive coaxial stubs are lossy, low-Q, elements."

Now I think I'll turn off the computer for a few days until the hostile 
reaction dies down :)

73,
Steve G3TXQ