Message-id: <70F8A86A0D5246048CFC9AEB13CC441C@MichaelSappPC>
From: "Michael Sapp" <wa3tts@verizon.net>
To: <rsgb_lf_group@blacksheep.org>
Cc: "John Langridge" <jlangridge@sbcglobal.net>
References: <18682173.20151206131730@chriswilson.tv>
 <5664461D.5010501@abelian.org> <774697463.20151206145008@chriswilson.tv>
 <56646A21.7040305@abelian.org> <005101d1305d$3c5af220$6601a8c0@user8e280af712>
 <566491EE.8020807@posteo.de> <E399A6AC1476419BAE2FAF6B1C17A451@MichaelSappPC>
 <5666BE1F.8010906@posteo.de>
In-reply-to: <5666BE1F.8010906@posteo.de>
Date: Tue, 08 Dec 2015 11:47:00 -0500
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Subject: Re: LF: Re: Tnx Stefan
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Status: O

Stefan (& All):  Yes, I am using a pair of reversible EWE antennas, sized 
5.5m tall and 21m long for NE~SW and SE~NW directional reception. The 
transformers are 10.5:1 on three BN73-202 cores glued together end to end. 
Four ground rods placed in a square pattern, one for each antenna 
transformer and one ground rod in the center.

 A common mode choke is used in the RG6QS feedline a few feet away from each 
antenna transformer.  Two feedlines for are used for each antenna and an A/B 
switch is used at both the SE and SW transformer locations to switch antenna 
A or B.  Two feedlines go to the receiver converter and the feed lines are 
grounded at midpoint between the antenna location and the receiver location.

At the receiving station, the two feed lines go to a coaxial, opposing 
phase, common mode choke. I terminate one output of the opposing phase CM 
choke with 75 ohms and other output of the opposing phase CM choke goes to 
the LF/MF converter via 75:50 ohm isolation transformer and LPF.

So I can reverse the direction of a single antenna at the station by 
changing the position of the 75 ohm termination resistor and isolation 
transformer coaxial jumper on the opposing phase CM choke.  I can also 
reverse the input of either of the two feed lines to the opposing phase 
common mode choke, which has a phasing effect for noise reduction which is 
somewhat frequency dependent from 10kHz to 500 kHz. I have to walk outdoors 
to change the A/B switches to select antenna A or B, but I need the exercise 
~:)

https://www.dropbox.com/s/xw0flkh343xhamg/LFMFEWE.JPG?dl=0

https://www.dropbox.com/s/5ygrqqv624c73y7/ewegnd.JPG?dl=0

The antennas are somewhat like a pair of K9AY loop antennas.  The EWE 
antenna was invented by Floyd Koontz
WA2WVL. This LF/MF version is similar to a reversible EWE antenna Floyd 
described in his February 1995 QST article,
"Is This EWE for You."

I also recently installed (8-2015) a low-impedance ground system for my 
residence AC power service, which also helped to reduce the local noise 
levels from LF through HF....

73 Mike wa3tts


----- Original Message ----- 
From: "DK7FC" <selberdenken@posteo.de>
To: <rsgb_lf_group@blacksheep.org>
Sent: Tuesday, December 08, 2015 6:25 AM
Subject: Re: LF: Re: Tnx Stefan


> Hello Mike,
>
> Thanks for watching and reports. I think you are my best DX to the west so 
> far. Do you use a directional rx antenna beaming to the east?
>
> 73, Stefan
>
>
> Am 08.12.2015 08:13, schrieb Michael Sapp:
>> Stefan:  Very Nice signals in EN90 this evening/morning....
>>
>> https://www.dropbox.com/s/nkmcnfjpd8iaad6/IMG_0038.JPG?dl=0
>>
>> https://www.dropbox.com/s/xupwslfyw8rx4py/IMG_0040.JPG?dl=0
>>
>> 2015-12-08 05:44   DK7FC   0.475682   -22   0   JN49ik   1   WA3TTS/2 
>> EN90xn   6636   298
>> 2015-12-08 05:54   DK7FC   0.475682   -23   0   JN49ik   1   WA3TTS/2 
>> EN90xn   6636   298
>> 2015-12-08 05:34   DK7FC   0.475682   -22   0   JN49ik   1   WA3TTS/2 
>> EN90xn   6636   298
>> 2015-12-08 06:04   DK7FC   0.475682   -23   0   JN49ik   1   WA3TTS/2 
>> EN90xn   6636   298
>>
>> 73, Mike wa3tts
>>
>