I will not be drawn into debates about scientific concepts that have 
long been well understood.
73, Jim K9YC
On 11/6/2020 12:58 PM, Artek Manuals wrote:
 
Jim
 Show me the ACTUAL antenna range pattern measurement data  with and 
without the common mode choke on a a similar antenna, with a reasonable 
SWR ( LESS THAN 1.5:1)  and the feed line has been brought down 
perpendicular to the plane of the antenna and I will concede you the point
Dave
NR1DX
On 11/6/2020 3:37 PM, Jim Brown wrote:
 
On 11/6/2020 12:28 PM, Artek Manuals wrote:
 The short answer is how tight you make the turns will have little 
real world effect. 
 
That short answer is WRONG.
Use the RG-8X I would probably use the #31 core over the
 43 . The poor mans 8 turns of coax 4-5" in diameter without ferrites 
will probably actually work as well. 
 
 Define "work." The important thing a choke should do is kill common 
mode current on the feedline that couples noise to the antenna and 
fills in nulls in the antenna's pattern. That "poor man's" solution 
won't do much for that. If "work" means it won't overheat, yes, it 
would "work."
 Depending on SWR and feed line dressing (always perpendicular to the 
plane of the beam the need for choke at all� is arguable
 
 It's arguable only if you don't understand the problem, or don't care 
about noise or the antenna's nulls.
73, Jim K9YC
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