One probe goes to your newly created ground. The other probe goes to a known good ground that is NOT tied to your new ground. In my case it is the power company ground.
The power company (at least in south Florida) has a ground rod at every power pole, tied to the high voltage neutral wire strung from pole to pole. This is also tied to the low voltage neutral wire which is the Center Tap on the secondary of the pole transformer feeding 1 to 10 houses. Three wires drop from the pole to the house all from the secondary of a 120-0-120 volt transformer providing two opposing phases of 120 volt power and 240 volt power.
There is a separate GROUND system inside the house which is usually derived from a metal water pipe that is connected to the city water main. If the water main is not conductive then a ground rod is used, hence the 1 ohm spec. The neutral (pole transformer CT) and the GROUND system are tied together inside the breaker box for the house.
Hundreds to thousands of direct lightning hits on the power lines is a daily occurrence in the Florida summer. This system usually prevents the average homeowner from seeing anything worse than a momentary flash or brownout during most storms. Exploding telephones, however were not uncommon when I was a kid in the 60's.
My house had the ground derived from the copper water plumbing, which went directly to the cast iron city system, so the about 20,000 houses were all electrically tied together by both the water and power delivery systems.
I simply used the power / water ground for one meter lead, and my buried metal for the other. The reading was about half an ohm either way.
Both. I had robbed the head off of a running engine which had been pulled from my car when I put in a turbo version. The headless engine sat in the yard for long enough that it would never run again, so....
I needed an anchor for a 12 foot dish antenna which would need to withstand the 60 to 80 MPH winds that a non hurricane storm system could deliver, so I made a big hole, dropped in an engine, some other metallic junk, four 1/2 inch threaded rods that came to the surface, and lots of concrete. All but the tips of the 4 rods, and the rebar ground connection were at least 8 inches below the surface. This was so that I could remove all obvious traces when it was time to sell the house.
A friend lost most of the electronics in his house when the power company neutral went open.
We had issues with another evil, the shared neutral system for internal house wiring. That system along with those stupid outlets where you strip the wire and stick it in a hole on the back virtually guarantee intermittent connections and blown up stuff.
how? this is how....Principles and testing methods of earth ground resistance - EE Publishers
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i worked in the Oil and Gas projects of Shell and Exxon, as a quality control engineer and earth testing is a very important thing, earthing rods 1.6 mm by 3 meters long are used and has a 10 ohm resistance, these rods are interconnected by 70 to 150 mm sq grounding cables, a network of cables joined together using exothermic welding...a grounding network is required to be 1 ohm or less for the client to accept the installation.
How about we pound a stake into the earth and then you'd have a gigantic one. Wire that baby up to the stereo and it's instant Audio Nirvana--just like that. It generates its effect just like homeopathy does! Of course, you would have to use an audiophile grade connecting wire. Make that detachable and the cable industry has a whole new product type to overcharge for.
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