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Brian,

I agree that approach has several problems, which are easily corrected. ?Without knowing the details of how long the coax, ground wires, etc. it is hard to quantify the degree of the problem. ?

1. ?A single ground rod can easily saturate the surrounding ground, at which point the charge remaining on the coax continues on directly to the radio.

2. ?Since the radio is connected to a separate ground rod, which is at a low earth potential (assuming it is some distance from the antenna's ground rod), all of the remaining current on the coax flows through the radio or tuner chassis en route to the "radio" ground rod. ??

3. ?It is likely the coax entering the structure will have a high enough voltage on the shield to arc over to nearby objects during an average strike of 18,000 amps and 2 microsecond rise time. Even outside, the coax can arc over to nearby objects, creating pinholes ( or worse) in the outer jacket, allowing water in.

To correct the problem:

1. ?Move the lightning suppressor to the ground strip near the shack (assuming it is outside, if not add one outside). ?This will divert any induced charges generated by a nearby strike that couple into the coax from bypassing the suppressor. ?

2. ?Use a bulkhead barrel connector where the lightning suppressor was originally, to ground the coax shield. ?Mount it to a copper or stainless steel bracket clamped to the first ground rod.

3. ?Connect the two ground rods with a #6 bare copper wire, buried 6" or as deep as possible. ?This will reduce the dynamic surge impedance of the ground system and be a parallel path that diverts much of the current from the coax headed to the shack.?

4. ?Depending on the type of soil, distance between ground rods, type of antenna, etc., add 1 or 2 additional ground rods connected with radial wires. ?Ground rods are cheap and last a long time (in most soil). ?The earth isn't a very good conductor, especially at >1 MHz. ?See pdf page 35 in the Polyphaser book.

5. ?Connect your radio ground system to the electrical panel ground, per NEC requirements.s

Steve, W3AHL