My experiences in a surburban set up (Bartlesville OK second QTH) are the same as Peters and others - some nice long 8ft earth rods spread out and about did most of the work, however empirically my QTH in Alaska (glacial morraine/clay and till) this did not work as well and I ended up with a large number of sort radials every few degress some 40m long (mostly for 80/160 gotta say), and a large earth mat of galvanised chicken wire covering an area of some 200ft x 100ft all interlaced. I know it rots but it worked well for a year.
In real terms, just with the sole aim at the time of increasing antennae current, it was diminshing returns over the amount of effort/cost, and I seem to recall I managed 21 ohms loss, most of which Im sure was environmental as I was in a cut out in Kincaid Park forest.
Looking back and what I know now I would have changes a few things in the antennae feed and earthing/matching arrangements too.
When I left AK I pulled up (with some mechanical assistance) sections of the galvanised mesh a length at a time and retuned and sure enough the losses increased but very slowly...
I did try 4 full size radials for 137kHz - all untuned and it did zip/nothing to improve the situation.
I did try earthing using a 200ft vertical well casing and this gave the exact same antennae current as all the above. I didnt have a bridge at the time but which I had.
Gotta say its every location is different and works well in some seems poor in others, but the general rule of as much in the air as high as possible, away from lossy objects, and as much in the ground seems a reasonable assumption, though Im now a little more concerned and thoughful about the reactances involved and voltages present on them insulated radials now after reading Jims notes.
I dont think Ill have to same problem back in AK in a few days as its got to be a loop, again over glacial overlay/till and some larger rocks...Im more concerned over the fire hazard as its very very dry at the moment and a burn ban in effect.
Thanks for the work - all very thought provoking....
Laurence BY3A KL1X
Teda China OM89UA
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