Ground connections to a tower
 

I have a TX455 tower that I am beginning to ground and I could use some
collective experience of the group. This is a 55-foot tower in a location
not especially prone to lightning. I am trying to be reasonable without
going overboard on grounding.

1. Where might I obtain the 1-inch nuts for the standard UST concrete stubs?
And stainless steel washers to match? My local Home-Depot type places seem
to stop at the 3/4-inch sizes.

2. There is no clearcut way to connect ground straps/wires to the tower. I
have ground posts about 30 inches from each of the three concrete bolts
holding the tower base. It seems reasonable to run a strap from a ground
post to the 1-inch concrete bolts holding the tower base bracket. There is
enough thread exposed above these to hold two (thin) SS washers and another
1-inch nut. This appears to be a convenient way to make the connection. I
assume the SS washers would be needed to fight corrosion from the copper
wire/strap to the zinc-dipped tower base.

3. I want radials for the tower (for a quarter-wave sloper). Would it be
reasonable to connect multiple radials to each of three ground posts and
then depend on the single wire/strap from the ground posts the three bolts
holding the tower base? This is for 160/80/40/30 meter operation.

Thanks,

Bill
W2WO

Too bad the grounding wasn't thought about sooner so that 1-3 ground rods could
have been put into the bottom of the hole dug for the base...

Bill Ogden wrote:

I have a TX455 tower that I am beginning to ground and I could use some
collective experience of the group. This is a 55-foot tower in a location
not especially prone to lightning. I am trying to be reasonable without
going overboard on grounding.

1. Where might I obtain the 1-inch nuts for the standard UST concrete stubs?
And stainless steel washers to match? My local Home-Depot type places seem
to stop at the 3/4-inch sizes.


Try a Semi truck repair facility. Lugs on most large trucks range from
1" to 33mm. Washers should be available too, though Stainless might be
a stretch.

2. There is no clearcut way to connect ground straps/wires to the tower. I
have ground posts about 30 inches from each of the three concrete bolts
holding the tower base. It seems reasonable to run a strap from a ground
post to the 1-inch concrete bolts holding the tower base bracket. There is
enough thread exposed above these to hold two (thin) SS washers and another
1-inch nut. This appears to be a convenient way to make the connection. I
assume the SS washers would be needed to fight corrosion from the copper
wire/strap to the zinc-dipped tower base.

3. I want radials for the tower (for a quarter-wave sloper). Would it be
reasonable to connect multiple radials to each of three ground posts and
then depend on the single wire/strap from the ground posts the three bolts
holding the tower base? This is for 160/80/40/30 meter operation.

Thanks,

Bill
W2WO

I can not recommend Ground Strap to ground the tower. Strapping makes
an excellent wick for rain water and will soon corrode. It is much
better to use a heavy copper wire. If you must use ground strap, be
sure to paint a heavy rubberized coating on all surfaces of the ground
strap.

Eric N7DLV

sideband wrote in message . com...
Bill Ogden wrote:

I have a TX455 tower that I am beginning to ground and I could use some
collective experience of the group. This is a 55-foot tower in a location
not especially prone to lightning. I am trying to be reasonable without
going overboard on grounding.

1. Where might I obtain the 1-inch nuts for the standard UST concrete stubs?
And stainless steel washers to match? My local Home-Depot type places seem
to stop at the 3/4-inch sizes.


Try a Semi truck repair facility. Lugs on most large trucks range from
1" to 33mm. Washers should be available too, though Stainless might be
a stretch.

2. There is no clearcut way to connect ground straps/wires to the tower. I
have ground posts about 30 inches from each of the three concrete bolts
holding the tower base. It seems reasonable to run a strap from a ground
post to the 1-inch concrete bolts holding the tower base bracket. There is
enough thread exposed above these to hold two (thin) SS washers and another
1-inch nut. This appears to be a convenient way to make the connection. I
assume the SS washers would be needed to fight corrosion from the copper
wire/strap to the zinc-dipped tower base.

3. I want radials for the tower (for a quarter-wave sloper). Would it be
reasonable to connect multiple radials to each of three ground posts and
then depend on the single wire/strap from the ground posts the three bolts
holding the tower base? This is for 160/80/40/30 meter operation.

Thanks,

Bill
W2WO

"Eric Snyder" wrote

I can not recommend Ground Strap to ground the tower. Strapping makes
an excellent wick for rain water and will soon corrode. It is much
better to use a heavy copper wire. If you must use ground strap, be
sure to paint a heavy rubberized coating on all surfaces of the ground
strap.

Eric N7DLV

Very good Eric. The other problem with "strap" (and we assume Bill Ogden
meant braid) is that braid is is a poor DC ground, and not even close to the
best choice for RF ground or bonding connector for lightning protection.
Braid is only specified for grounding of vibrating machinery and other
flexible requirements. Avoid any kind of braid for radio or bonding uses if
possible, especially if it is not tinned.

SS washers between copper and galvanized tower will not isolate the
connection at all. Acid rain will wash the copper oxides all over the tower
studs as if it were connected directly.

Obtaining the best tower and coax shield grounding possible is important not
only for lightning protection, but for protection from static charges which
all towers and antennas are susceptable to. The RF grounds and radials etc
must be an integral part of any lightning protection scheme. The only
reminder is to avoid allowing a downconductor from rooftop air terminals,
masts or tower from bonding to an RF radial component *until* the
downconductor first connects to a deep ground rod.

Jack


sideband wrote in message
. com...
Bill Ogden wrote:

I have a TX455 tower that I am beginning to ground and I could use
some
collective experience of the group. This is a 55-foot tower in a
location
not especially prone to lightning. I am trying to be reasonable
without
going overboard on grounding.

1. Where might I obtain the 1-inch nuts for the standard UST concrete
stubs?
And stainless steel washers to match? My local Home-Depot type places
seem
to stop at the 3/4-inch sizes.


Try a Semi truck repair facility. Lugs on most large trucks range from
1" to 33mm. Washers should be available too, though Stainless might be
a stretch.

2. There is no clearcut way to connect ground straps/wires to the
tower. I
have ground posts about 30 inches from each of the three concrete
bolts
holding the tower base. It seems reasonable to run a strap from a
ground
post to the 1-inch concrete bolts holding the tower base bracket.
There is
enough thread exposed above these to hold two (thin) SS washers and
another
1-inch nut. This appears to be a convenient way to make the
connection. I
assume the SS washers would be needed to fight corrosion from the
copper
wire/strap to the zinc-dipped tower base.

3. I want radials for the tower (for a quarter-wave sloper). Would it
be
reasonable to connect multiple radials to each of three ground posts
and
then depend on the single wire/strap from the ground posts the three
bolts
holding the tower base? This is for 160/80/40/30 meter operation.

Thanks,

Bill
W2WO

. com...
Bill Ogden wrote:

I have a TX455 tower that I am beginning to ground and I could use
some
collective experience of the group. This is a 55-foot tower in a
location
not especially prone to lightning. I am trying to be reasonable
without
going overboard on grounding.

1. Where might I obtain the 1-inch nuts for the standard UST
concrete
stubs?
And stainless steel washers to match? My local Home-Depot type
places
seem
to stop at the 3/4-inch sizes.


it probably is not the cheapest, but http://www.andrew.com/catalog38/ has
pretty much what's needed in the way of grounding kits and tower hardware.

most radio and TV stations seem have some of that stuff laying around left
over from an install. odds and ends of hardware and clamps. got any buddies
that are broadcasters?