Earthing Madness - how far have you gone?

[Bluesboy65]

Hi Bill,made a massive difference,in HiFi terms bass was cleaner,treble less harsh,but more so than that,there was no mush on the mains,it was fundamentally better,you couldn't get the sort of improvement by buying a piece of equipment,pity I can't do it were I am know.

[BilliumB]

Thanks Ian, really interesting to hear what worked for you.

I'm planning on a dedicated consumer unit and radial for the hifi, but also wondering about the most effective earthing setup - I'm out in the sticks on a TT (local earth spike) system (rather than on PME like most people) and currently have a single earth spike that's been there for some years.

I've got plenty of space around the house, and a 3 tonne digger, so am considering something significant on the earthing front. One thing I'm wondering about is a line of well spaced spikes following the ditch at the side of our lane - this should keep them well watered! Other options include some form of buried earth mat.

At the moment I'm trying to find out what has worked for other people. One suggestion I've had from someone in the industry is to put in a 'rf earth' using thick coax connected as follows - screen and centre core connected together and to earth, centre core connected to an earth terminal, or outer on an unused phono at the kit end - the idea being a low impedance route to earth for higher frequency noise that will 'see' a simple 16mm2 earth cable as high impedance. A key issue is making the connection to earth using something that won't corrode and act as an rf detector. One option I'm considering is a big stainless steel plate thrown down into my well! For safety reasons it might be a good idea to add a suitably rated capacitor in the line.

At the moment I'm still considering the options before all the upheaval, probably some time next year!

Cheers. Bill

[Bluesboy65]

One last thing,the consumer unit that Russ Andrews sells can be bought for a third of the price,good luck with your project.

[Sonority]

If you really want to do it right - then give Chem Rod a call. They have a Uk side as well.
Earth rods should not just be hammered in willy nilly - they need to be correctly spaced so as not to interfere with each other, and the distance apart depends entirely on what they are going into resistance wise.
GAF (ground augmentation fill) can help (think kitty litter). Also - knocking them in as deep as you can can actually make matters worse - not better.
Again you really need to know the resistivety of you sub soil. It is NOT an easy subject to get right, it is VERY easy to get it wrong!

Chem Rod really know their stuff - I travelled all the way to the States to help a friend to fit his. It worked, very, very well.
If your going to do it - do it right and get all of the facts you need before you start. They are not that easy to find in all honesty.
Just using hundreds of rods simply isn't the way to go.

[BilliumB]

Thanks Stephen

Yes, I've been reading up about the issues, min spacing of rods = 2*length, reduced impedance from use of bentonite or similar etc.

Do tell us a bit more about your friend's setup, what you did and how it improved things.

Thanks, Bill

[Light Dependant Resistor]

Thanks Ian, really interesting to hear what worked for you.

I'm planning on a dedicated consumer unit and radial for the hifi, but also wondering about the most effective earthing setup - I'm out in the sticks on a TT (local earth spike) system (rather than on PME like most people) and currently have a single earth spike that's been there for some years.

I've got plenty of space around the house, and a 3 tonne digger, so am considering something significant on the earthing front. One thing I'm wondering about is a line of well spaced spikes following the ditch at the side of our lane - this should keep them well watered! Other options include some form of buried earth mat.

At the moment I'm trying to find out what has worked for other people. One suggestion I've had from someone in the industry is to put in a 'rf earth' using thick coax connected as follows - screen and centre core connected together and to earth, centre core connected to an earth terminal, or outer on an unused phono at the kit end - the idea being a low impedance route to earth for higher frequency noise that will 'see' a simple 16mm2 earth cable as high impedance. A key issue is making the connection to earth using something that won't corrode and act as an rf detector. One option I'm considering is a big stainless steel plate thrown down into my well! For safety reasons it might be a good idea to add a suitably rated capacitor in the line.

At the moment I'm still considering the options before all the upheaval, probably some time next year!

Cheers. Bill

Hi Bill
I have had experience with AM radio grounding in semi tropic / wet season area. We had great success with deep grounding where nearly
as good as you can get was achieved at 20 meters depth, and is assisted with graphite powder that is poured in
like a concrete slurry. Whilst this worked for protecting transmission assets, there are other approaches based on the
individual sites soil resistance, climate and what is being protected.

Also how the rod material should be bonded with exothermic welding and its construction vs time are all factors
http://www.erico.com/public/library/fep/LT30323.pdf

A few hours studying this fascinating subject, including how to determine soil types and electrical resistance of soil is well worth while.
Your local council other than being experts at collecting rates- usually their main focus, may have some prior knowledge of your area that might assist

Cheers / Chris

[BilliumB]

Thanks Chris

I've read a bit about exothermic welding but not sure whether my electrician would have the kit for it (I'll investigate - he does some industrial stuff), or whether something suitable could be hired. I'd been wondering about making a more normal 'clamp' connection using cleaned, deoxidised, components, and then covering in something like Denso tape, silicon or similar.

Any thoughts on the 'rf' or higher frequency earth - this seems logical to me as the normal earth cables, spikes, mats etc are likely to have quite a high impedance to the sort of noise frequencies that, I assume, will make a difference.

Cheers. Bill

[Light Dependant Resistor]

Thanks Chris

I've read a bit about exothermic welding but not sure whether my electrician would have the kit for it (I'll investigate - he does some industrial stuff), or whether something suitable could be hired. I'd been wondering about making a more normal 'clamp' connection using cleaned, deoxidised, components, and then covering in something like Denso tape, silicon or similar.

Any thoughts on the 'rf' or higher frequency earth - this seems logical to me as the normal earth cables, spikes, mats etc are likely to have quite a high impedance to the sort of noise frequencies that, I assume, will make a difference.

Cheers. Bill

Hi Bill
If welding is too difficult or beyond your electrician, then clamping using threaded tops and nuts or car battery clamps.
Remembering everything is added length and wears out, with stainless steel being the best of the bunch for longevity.

I would choose a spot that is not dry if that is possible, try and get a single hole bored to 8 meters if that is possible - that's a long way down ,
obtain stainless steel rod with threaded top section. Treat the bored hole with graphite powder known commercially as GEM
http://www.erico.com/part.asp?part=GEM25A If GEM is not available, try and source salt to treat the ground

The cables and their length attaching are of course pivotal to success, and in radio work we used very heavy solid copper strap of only
2 meter length which was more to do with low impedance lines for lightning protection and the current a 2.5 kw transmitter was drawing.
We used a 20 meter hole at the AM mast itself, then another 25 meter hole just outside the equipment hut, both had solid threaded section rods
and short cables attaching back to equipment chassis.

In your circumstance if the commercial hardware is too expensive, use car battery cable.

Here are a few tips that might help to adapt to your circumstance that possibly is not as strict:

In radio station equipment racks, if the engineer has really prepared the site correctly there will be a earth rod directly under the rack - exactly where it is needed.

Mats and just below ground radiators, known as radials are used to propagate AM frequencies rather than protection, so you are quite right these are high impedance devices
using the earth to reflect in this case medium wave frequencies.

Be prepared to maintain connections, and provide insulation from weather events.

Cheers / Chris

[BilliumB]

Thanks Chris

Some food for thought! Your figures are really significant, but I'm not surprised having scanned through the Motorola manual on grounding for radio stations.

In reality, I'm going to have to compromise. The HiFi kit is about 15m from the nearest reasonable position for the first earth spike - I'm certainly not going to achieve the close proximity that would be most beneficial. I've got a hole borer used for fence posts, but that will only go down about 1.5m. I had been wondering about using the digger to make a 'trench' earth which would probably use copper plate or strip in a mesh format - improved by the use of graphite powder, bentonite or similar. I was also wondering about a 2-3m spike (or series of spikes) driven down into the bed of a stream about 30m from the hifi. Also utilising the water well in some way - it's about 15m from the hifi.

What are your thoughts on using coax to earth as a low impedance route (in addition to the more normal safety earth spikes and bonding) - it seems to me that most of the rest of the 'simple' earthing will have little (or minimal) beneficial effect on low(ish) level noise signals, especially given the cable lengths necessarily involved?

It's an interesting problem isn't it!

Cheers. Bill

[Light Dependant Resistor]

Thanks Chris

Some food for thought! Your figures are really significant, but I'm not surprised having scanned through the Motorola manual on grounding for radio stations.

In reality, I'm going to have to compromise. The HiFi kit is about 15m from the nearest reasonable position for the first earth spike - I'm certainly not going to achieve the close proximity that would be most beneficial. I've got a hole borer used for fence posts, but that will only go down about 1.5m. I had been wondering about using the digger to make a 'trench' earth which would probably use copper plate or strip in a mesh format - improved by the use of graphite powder, bentonite or similar. I was also wondering about a 2-3m spike (or series of spikes) driven down into the bed of a stream about 30m from the hifi. Also utilising the water well in some way - it's about 15m from the hifi.

What are your thoughts on using coax to earth as a low impedance route (in addition to the more normal safety earth spikes and bonding) - it seems to me that most of the rest of the 'simple' earthing will have little (or minimal) beneficial effect on low(ish) level noise signals, especially given the cable lengths necessarily involved?

It's an interesting problem isn't it!

Cheers. Bill

Hi Bill
If 15m is it, then go with that and bore a hole as deep as you can using GEM to treat the ground or similar.
RF 50 ohm cable RG 213 or larger would be interesting to use as a psuedo ground transmission line, it would be an unusual application
to harness the properties of coax to minimise loss over what is a connection to earth itself, so I see where
your coming from. Given distance is relatively short car battery cable, or solid copper rod should be sufficient
i will have a think about the coax idea.

Cheers / Chris