Return-Path: Received: (qmail 25409 invoked from network); 17 Dec 2002 12:41:52 -0000 Received: from marstons.services.quay.plus.net (212.159.14.223) by mailstore with SMTP; 17 Dec 2002 12:41:52 -0000 Received: (qmail 8156 invoked by uid 10001); 17 Dec 2002 12:41:53 -0000 Received: from post.thorcom.com (193.82.116.70) by marstons.services.quay.plus.net with SMTP; 17 Dec 2002 12:41:53 -0000 X-SQ: A Received: from majordom by post.thorcom.com with local (Exim 4.10) id 18OH2W-0002yZ-00 for rsgb_lf_group-outgoing@blacksheep.org; Tue, 17 Dec 2002 12:41:36 +0000 Received: from [24.153.64.2] (helo=smtp.comcast.net) by post.thorcom.com with esmtp (Exim 4.10) id 18OH2V-0002y4-00 for rsgb_lf_group@blacksheep.org; Tue, 17 Dec 2002 12:41:35 +0000 Received: from yourw92p4bhlzg (pcp02064100pcs.nrockv01.md.comcast.net [68.83.215.165]) by mtaout05.icomcast.net (iPlanet Messaging Server 5.2 HotFix 1.07 (built Nov 25 2002)) with SMTP id <0H7900JDVKHK0S@mtaout05.icomcast.net> for rsgb_lf_group@blacksheep.org; Tue, 17 Dec 2002 07:39:21 -0500 (EST) Date: Tue, 17 Dec 2002 07:39:22 -0500 From: "Ralph Lane" To: rsgb_lf_group@blacksheep.org Message-ID: <001801c2a5c9$533c5e70$0000a398@yourw92p4bhlzg> MIME-Version: 1.0 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 X-Mailer: Microsoft Outlook Express 6.00.2600.0000 X-Priority: 3 X-MSMail-Priority: Normal References: <5.1.0.14.0.20021217112756.02a24720@POP3.freeler.nl> Subject: Re: LF: EARTH RESISTANCE Content-Type: text/html; charset=windows-1252 X-Spam-Status: No, hits=0.4 required=5.0tests=BIG_FONT,EMAIL_ATTRIBUTION,FROM_ENDS_IN_NUMS, HTML_COMMENT_UNIQUE_ID,MAILTO_LINK,REFERENCES, SPAM_PHRASE_00_01,SUPERLONG_LINE,USER_AGENT_OEversion=2.42 Sender: Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Content-transfer-encoding: 8bit
Sorry about that. Here is the test of my message:
 
Ralph
 

"Ground Conductivity Test" is from the ARRL Antenna Handbook...

The book I have is from 1994....and it is on page 27-35 that's chapter 27 page 35........

Conductivity Soil, Measurement of....

It takes 4 rods.......9/16" diameter and 14 inches long these 4 rods are driven into the ground 18 inches apart in a straight line......drive them in 12 inches...

One side of the 120 AC line to a 100 watt light bulb...the other side of the bulb to a 14.6 ohm resistor.........they say to make up the resistor by paralleling 5 of them...3 of which are 68 ohm 1 watt....the other 2 are 82 ohm 1 watt......then the other end of the resistor goes to rod #1 .......the other side of the AC line goes to the farthest rod.....

You now have two AC voltage test points......V1 is across the resistor. V2 is voltage measured between rods #2 and #3.....

In general these two voltages they say should be from 2 to 10 volts......

Formula for calculation is......

C = 21 x V1/V2
 

This gives you the Millisiemens per meter

----- Original Message -----
Sent: Tuesday, December 17, 2002 5:35 AM
Subject: Re: LF: EARTH RESISTANCE

To All from PA0SE

Mike, G3XDV, wrote:

I think this is why people are confused. I believe that Dick measured
"system loss", which includes all losses except inductor loss. Calling it
"earth resistance" simplifies the situation too much. Plainly a wet
environment will increase leakages.

I indeed measured the total resistance of the aerial system (minus the coil loss) as I have explained in my e-mail. I agree with Mike that "system loss" would have been a better expression than "earth resistance".  


Has anyone measured earth resistance alone under different conditions? If I
recall correctly, this can be done with three earth stakes and Kirchoff's
laws.


Indeed, but it usually done at 50Hz. To be meaningful at LF the measurement should be performed at an LF frequency. But I'm afraid that will not be so simple.

73, Dick, PA0SE