[CQ-Contest] What am I to think?

[donovanf at starpower.net]

Hi Doug, 


Your system should be performing superbly, something is wrong. In my 
experience there's almost nothing you can do to cause a Beverage to not 
perform properly other than installing it over highly conductive soil 
(e.g., a salt march), installing it close to tall towers, or a variety of possible 
installation errors. 


The following questions relate to the pattern you should have achieved. 


How high are your Beverages? 


What is your ground system at each end of your Beverages? Every 
ground should be independent, no shared ground rods should be 
ever be used. 


Are you sure that you wired all of your W8JI transformers exactly the 
same? If you accidentally flip the polarity of either transformer winding 
you will have big problems when you phase two Beverages. 


Did you use an MFJ-259 or another suitable antenna analyzer to verify 
proper impedance vs. frequency plot for each Beverage? W ith the W8JI 
transformer, properly terminated Beverages should be close to 75 ohms 
and the impedance will vary somewhat with frequency, the amount of 
variation as you sweep in frequency is a function of how well terminated 
the Beverage is. 


Did you check the impedance of each of the two phased Beverages 
at the end of each RG-6 feedlines before you connected them together 
with your T-connector? The impedance at the end of each RG-6 should 
be almost exactly identical when you use a simple T-connector to join them. 
A better approach is to use a 75 ohm "magic-T" combiner (aka 3 dB splitter) 
to connect them together rather than a T-connector. 


The impedance of your unterminated Beverages should vary drastically 
with frequency. It may be necessary to trim the length of your unterminated 
Beverages to get a reasonable VSWR. 


Have you tested the directivity of your Beverages at the top end of the 
AM broadcast band? You should observe excellent directivity and 
at night you should be able to switch among three or four stations on the 
same frequency. 


What are you using as an antenna switch to select among the Beverages? 
Many antenna switches have poor isolation among the ports.which will 
significantly degrade the performance of your Beverages. 


73 
Frank 
W3LPL 

----- Original Message -----

From: "dt" <wd5r at ozarkisp.net> 
To: cq-contest at contesting.com, donovanf at starpower.net 
Sent: Monday, May 18, 2015 12:13:16 PM 
Subject: Re: [CQ-Contest] What am I to think? 

Frank, in responding to your request, 
I feel much same way I would 
had I received a request from Steven Hawking 
asking what I had seen in the Arkansas sky last night. 
................... 

We basically used the diagram in Low-Band DXing, 3rd ed. 
page 7-31 for start. 
In-phased wires, 850ft long, approx 390ft spacing, 
and terminated. 

Isolation transformers Fairrite 2873000202 
2 to 5 winding, (thanks to W8JI ) 

No transformer at junction of RG6 feed lines. 
Yes, I'm sure I lose something without proper 
matching.. 

All RG6 brought to the house buried 
in 1/2 Polyethylene tubing . 

We have six pairs with that arrangement, 
2 to West, 2 to NW, and 2 to NE. 

We also have same setup toward north, 
except not terminated. 

Single wires toward SE and SW 

All shields grounded at house entrance. 
Our switching at the desk allows us 
to keep both receivers in our K3 happy. 

Most of you that read this will recognize it is an 
Arkansas chicken farmer installation and there is 
nothing special about our arrangement. 

The hard part was wading through chicken sheet for 
15 years in order to come up with the pasture space. 

More detail might cause you to fall out'a your 
chair laughing or more likely, for you 
engineers, serious stomach pain. 

Situation could be summed up by suggesting 
you put an underfunded car in a NASCAR race 
with an 83 yr old farm hand as driver. 

Doug, n5ect 
2nd in command at WD5R 
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