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				 Is It double bazooka less noisy? 
 
			
			MiguelThere are "eyewitness accounts" of all sorts of foolishness.
 
 If you build it perfectly a bazooka will show a decrease in SWR over a very
 small range either side of resonance (SWR = 1:1) when compared to a dipole.
 This is completely useless except as an academic exercise.
 
 Here's how it works:
 The antenna is a parallel-resonant network (the bazooka) in parallel with a
 series-resonant network(the dipole).
 The parallel resonant (tank circuit) network stores energy and will
 oscillate at it's DRIVEN frequency when driven near resonance, so it stores
 the energy that would otherwise be reflected as long as it oscillates. Go
 too far from resonance and it quits oscillating. This effect manifests
 itself at SWR of 1.2:1 or lower. It flattens the SWR curve very near
 resonance.
 The 2:1 bandwidth is unaffected except by the additional loss of the tank
 circuit sitting across the dipole feed point.
 
 What Walter Maxwell showed explicitly is that any increase in SWR bandwidth
 is entirely due to loss, if I recall correctly.
 
 So all the trouble of building a bazooka with both legs and the dipole
 resonant at exactly the same frequency is a waste of time.
 A simple dipole works a bit better and is *MUCH LESS* work and expen$e.
 
 73
 H.
 NQ5H
 
 
 "lu6etj"  wrote in message
 oups.com...
 
 Dear friends:
 
 Thank you very much for your answers.
 
 First of all: I agree with you, but my agreement is inductive, not
 experimental because I have not made my homework with that antenna...
 ..
 I knew the excellent article of Walter Maxwell, I am a fan of Maxwell,
 (both Maxwells) from their famous article "Another look on reflections"
 
 But do I think: is it possible that all those friends that are
 enthusiastic of the bazooka are affirming foolishness? They say: -With
 the bazooka we listen stations that we don't with the plain dipole, and
 this affirmatiotn point to a better SNR...
 
 I think that it must have something true behind so many similar
 statements. In the radio club of my area they say to have compared one
 against another with clearly favorable results to the bazooka.
 
 I thought...: A plain dipole is not a monoband antenna, it is, in fact,
 a multiband antenna, it receives all the frequencies. But do let us
 imagine a plain dipole that had connected on its terminals a couple
 high Q tuned circuits. That system it would be really "monoband"...
 then, if we connect such a system to a poor receiver Would not it
 improve the reception perhaps?, eliminating by that way possible
 saturation sources or intermodulación noises.
 Such a system, empirically it would seem a practically "more silent
 antenna" and it would explain, perhaps, the some results obtained by
 the colleagues. I say this because it is said that the bazooka
 possesses a syntony effect that transforms it into a true monoband
 device (I am not sure of it).
 
 It is only an arbitrary example of possible alternative explanations
 that, without violating the fundamental principles, can be
 compatibilized with the experiences of so many colleagues that
 sympathize with this antennas(some of which deserve my technical
 respect).
 
 I thank all your answers but I continue to the search of some
 explanation that endorses all the facts, just as the formidable article
 of Walter in reference to its bandwidth...
 
 I am for sure some of you will be able to help me to find a convincing
 explanation.
 
 Thank you very much in adavnce
 
 Miguel Ghezzi (LU 6ETJ)
 
 
 
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