Topband: Strange resistance between Beverage ground rods

[Herbert Schoenbohm]

Thanks to all that have given tips on this. I was using a Fluke 77  in 
the low resistance automatic range and as Lee K7TJR pointed out even a 
small induced voltage was enough to drive the resistance reading up to 
20K Ohms.   I made additional measurements with my Sperry DM-4100 and an 
analog VOM and they were all different.  On the DC scale I measured .6 
volts om respect to ground.  this would be enough to sent the Fluke 
nuts. When using the Sperry's diode settings I got -.243 in one 
direction and no reading in the other.  Maybe I was going nut or Tesla's 
theories of extra scalar potential are really valid. Tomorrow I will run 
out a line cord and take along a 12VAC transformer and feed the two 
wires of the Beverage against ground while measuring the actual return 
voltage.
Then I will calculate the voltage drop of the sire to ground loop and 
calculate the resistance.  I know this may sound crude but I should get 
a more usable value. what had me worries about the far end 3 ground rod 
termination is that between wires the resistance measurably 40 ohms for 
a 900 foot Beverage which should be fine. I guess since the WD-1A is a 
balance medium any induced voltage would be cancelled out. There is a 3 
phase 14KVA system that passed parallel to the road near where the 
Beverages are terminated maybe there is enough DC rectified currents 
somewhere to give me the false reading on my Fluke.

My initial test results suggested that the far end ground connection was 
gone but that was not the case.  Wading my way through waist high saw 
grass for 900 feet trips is not fun.  My son came up with a excellent 
suggestion of buying a quad copter with video on e Bay and making my 
Beverage wire inspection will siting in the shack.  As anyone every 
tried that?  Sounds like fun.   Plodding thorough waist deep snow in the 
winter, not a problem here, is a not a very easy chore.


Herb, KV4FZ




On 11/15/2016 12:55 PM, Lee STRAHAN wrote:
> Hello Herb and fellow Top Banders,
>     When I had Beverage antennas here I was never able to read the ground resistance here as well. The reason it did not work here is there was actually a small DC voltage difference between grounds apparently developed by galvanic means or currents in the earth. This voltage does not allow a DC resistance meter to read correctly.
>     As a side note there is a 1,000,000 volt DC power generation line running from Celilo Oregon to Sylmar California that uses the Earth as one conductor. Its no wonder here there is DC across portions of the ground. Just look up Celilo converter station if you are curious. 3200 megawatts transported from Oregon to California through the ground! This line is within 20 miles of my farm. This may or may not be partly responsible for the DC difference on mine or others Beverage antennas.
> Lee  K7TJR   OR
>
>
> I have reflection transformers at the end of every two wire Beverages which I try to test by measuring the wires on the feed end. I remove the transformer from the two wire WD1-A and check the resistance between the two wires which tells me that through the reflection transformer I have continuity. It measures about 40 ohms wire to wire, this is done when I notice any performance change of the antenna. Now come the next test that baffles me completely.  When I measure from either wire to my ground rods alone, to see what the return resistance is, I get reading
> in the vicinity of 20K  across the 900 foot run.    I understand that if
> the reading was very low it would defeat the whole Beverage principle.
> But is 20K Ohms reasonable, very good, or marginal?  I use three foot foot rods at either end and when I pull one out yesterday before moving it the bottom 1/4 was moist and muddy. That Southern end of several reversible Beverages  is located about 100 feet or less from a salt marsh or salt pond.  I also have to such antennas made up of ladder line a DX Engineering components.  They all appear to be working well even though large grass has reach and covered portion of some of them.
>
> But my question is what is a reasonable or good return ground resistance for a 600' or 900' Beverage.  I haven't found any sources of information expect the saying that the higher Resistance the better. Is this correct?
>
> Herb Schoenbohm, KV4FZ
>
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