Sent from my iPhone
> On Oct 18, 2019, at 9:36 AM, Roger D Johnson <n1rj@roadrunner.com> wrote:
>
> The ham reflectors are full of accounts
> of putting in X number of ground rods, measuring the resistance at power line
> frequencies and being fooled into thinking they have a good lightning ground.
>
> 73, Roger
> _________________
Sorry Roger, but I don’t recall reading the accounts you assert the
“ham reflectors are full of.” Seems to me what I mostly read are
postings about three types of antenna grounds: (1) high Z grounds
intended to bleed off static electricity and thereby protect receiver
front ends, and (2) low Z grounds made of heavy gauge wire intended to
absorb the EMP from nearby lightning discharges, and (3) super-robust
low Z single point grounds intended to safely dissipate the energy
from direct lightning strikes.
At my station I have all of the above, depending on the situation. For
example, my 70 foot Sky Needle falls in the third category. It has 8
buried 80 ft radials of 4AWG copper wire fanning out from the base,
with an 8 ft ground rod attached to each radial, spaced roughly 16 ft
apart - 40 ground rods in all. This setup has absorbed several direct
strikes with no damage to connected equipment.
All of my grounds are based on information I obtained from ham
reflectors, including this one.
73,
Jim w8zr
_________________
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