Topband: A Bit Off Topic

[Mike Waters]

I don't doubt that one bit, Tom. But since I have a 30-mile-long 7850 volt
line between my 15 kVA pole pig and the Mt. Vernon substation, I think what
I jerry-rigged was worth doing. (Especially since Ozark Electric in their
infinite wisdom removed all the older spark gaps when they installed the
newer ceramic-encased "lightning arrestors". IIRC, that's about the time
when lights in the house began to flare up in brilliance during some
thunderstorms. You be the judge, but I don't think that's necessarily all
common mode. :-)

I just cannot afford a decent $600 outdoor surge suppressor. I was
contemplating building my own using GDTs, MOVs, TVS diodes, etc. but it
wouldn't have saved very much at all.

That outdoor meter pole(1), the breaker panel inside the house(2), and the
location of my 160m station where all the coax enters(3) are --viewed from
above-- points on a large triangle with all sides ~30' long. Yeah, that's
bad. The only way I could figure out how to bond all that together would
take a LOT of copper and/or a lot of re-routing of coax. As it is now, when
there's lightning in the WX forecast, I disconnect all the coax coming in
through the basement wall behind the radio. (All that coax is already
grounded at the entrance with #4 or #6 CU and two 8' copper-clad rods.)

I installed that all years ago, when I had little knowledge of bonding
grounds. I guess I should just move the ham station across the basement, as
close as possible to the house panel on the ground floor.

But doing that won't protect all the other devices in the house.

FWIW, the ground rod for the house panel (installed before I bought this
place) is worthless. It's driven into well-draining coarse limestone very
close to the foundation and has high resistance to the earth.


BTW, here are the claimed specs on that Sycom meter-base "surge suppressor"
and (IMO) laughable "warranty". Amazing.

http://sycomsurge.com/~sycomsur/images/products/SYC-240B.pdf

http://forums.qrz.com/showthread.php?474017-Effectiveness-of-Sycom-meter-base-surge-suppressors&p=3454751#post3454751

http://sycomsurge.com/catalog/Meter_Socket_Protector-11-1.html

Any further suggestions would be most welcome.

73, Mike
www.w0btu.com

On Sat, Jun 27, 2015 at 2:34 PM, Tom W8JI <w8ji at w8ji.com> wrote:

>
> ... Although there can be exceptions, virtually all damage is common mode
> that flows in parallel on bundles between things. (The same is generally
> true for RFI.)
>
> The vast majority of protection comes from a common entrance ground bond,
> where everything entering a system, or everything entering an equipment
> hub, enters through one point where "grounds" are common bonded.
>
> The most prolific damage, and the worse sensitivity to damage, occurs when
> widely separated things enter without being brought together at one point
> and bonded.
> ...
> When stations have repetitious or severe damage, it is almost always a
> poor layout or poor wiring techniques. The best protection devices won't
> fix that.
>