[TowerTalk] Strange happening with 10 Meter Beam

[TexasRF at aol.com]

Hi Herb, your problem sounds very much like high coax loss, in spite of it  
being new.
 
A quick check on this is to do a vswr check on a different band where you  
would expect a high vswr. Such as 20m for example, you would expect the vswr 
to  be 5 or 10 to 1. If there is excess loss in the line, the expected high 
vswr  would be greatly reduced. In fact, you can actually determine the 
loss by the  amount the vswr is improved over expected.
 
An extreme example of this is my 1296 MHz dummy load: a 100 ft length  of 
RG213 with the far end unterminated has enough loss to reduce the infinite  
vswr to less than 1.3 to 1 or so.
 
73,
Gerald K5GW
 
 
 
 
 
 
 
 
In a message dated 10/28/2015 8:30:52 A.M. Central Daylight Time,  
herbert.schoenbohm at gmail.com writes:

For the  CQ WW I put up a 5 Element HyGain 10 meter beam(LJ-105CA)  I 
double  and triple checked all the element lengths and the VSWR is so low 
across  the band it really excited me.  It also scares me a bit as up in 
the  air the VSWR is never above 1.3 to 1 from 28.0 to 29.5.  The problem  
is that signals are very weak on non existent when compared to my 3  
element quad at 80 feet which was the only antenna that worked on ten  
during the contest and after.. ( The yagi is one a separate tower at 50  
feet)

Here is what I have on it.
New piece of LMR-400 with good  connectors fed directly to the insulated 
(Hy Gain cup type)  director.
The beta rods were missing so I use the direct feed to each  director. 
(OWA type matching idea)
I moved the first director slightly  closer to the driven element to 
obtain the correct match at 28.4  Mhz
Everything looks good but the 10 meter antenna is about as good as a  
dummy load.


I have been building yagi's for over 50 years and  have never had such a 
strange problem.  Even a beam with half the  driven element missing after 
a hurricane could hear something but what I  have up can't.

Before I take it down I ask if anyone else had  experiences with this 
problem.  It must be something very simple but  I have checked everything 
I can think of and still no joy  here.


Please let me know
Herb Schoenbohm,  KV4FZ
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