Living on extraordinarily acidic soil (pH ~4), there's little point in driving a '10 foot stake' made of copper-clad iron into the ground here; it will simply rot away in months.
Instead, I use a 1.5m-long 15mm copper pipe, driven into the soft, acidic and highly-conductive ground. The connection to the ground bus is made with about 1.5m of hand-cut solid copper banding of about 15mm width. That's the shortest I can physically make it here.
***PLEASE NOTE: PROTECTIVE MULTIPLE EARTH SYSTEMS***
Before you go hammering lots of earth rods into your garden, please make sure you read this free RSGB leaflet carefully. If you are not sure of anything, contact both your electricity provider and a qualified electrician. Your house could burn down, possibly with your insurance being invalidated, if you do something that you either don't understand or that isn't according to the regulations, or both.
All this earthing work led me to stick a lightning arrestor onto the earthing bus. It claims to have 'less than 0.1dB insertion loss', which I'm sure that, at HF, is probably true.
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| Under WSPR test - a common lightning arrestor unit. |
Whilst I can't quickly put an obejctive figure on the losses - that will have to wait for more time to be available - I can run WSPR on a WSPRlite unit at low power (100mW) through the arrestor, and see whether the results cause any concern, relative to past extensive testing, and to other stations running twice the power.
After just 18 hours of transmissions (40% duty), it's clear that passing the puny 100mW through the arrestor doesn't seem to affect the outstanding performance of my twin-fed delta loop. Clearly, there is bound to be some attenuation, but not at a level that makes any material - or even detectable - difference.
So it seems that I can leave the arrestor permanently in place. If you have many antennas, it's best to use an arrestor for each one.
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