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Loss in splitters

I live in the city, but still don't get 100% reception. You think one of these mounted in the attic would work ok? I'm only trying to get stations from a tower that's maybe 20 miles away.

Ed
 
Living where I do, you don't need 8' of rod to get a good ground. We get 70"-80" of rainfall a year. Just not a problem.
 
whoaru99 said:
Paul, just one thing.

I think by code that ground rod should be driven fully below ground level and buried. Could be wrong on this, but almost sure I read that somewhere.

I won't tell if you won't, but just thought I'd mention it.
Click to expand...

I worked 12 years in cable tv and code required that we used 8 foot ground rods. I'm surprised they had 3 footers at Radio Shack.

Paul
 
Hooked everything up yesterday (man it was so hot and humid before the rain/cold front). Reception and signal strength is a lot better. Some stations that were 7's are now 9's on the signal strength meter. I love pegging the meter!

Just curious, will hooking up the ground improve sound? I've read that it does.
 
whoaru99 said:
Paul, just one thing.

I think by code that ground rod should be driven fully below ground level and buried. Could be wrong on this, but almost sure I read that somewhere.

I won't tell if you won't, but just thought I'd mention it.
Click to expand...

As an electrician I can tell you that you are correct for the primary ground from the electrical panel. However that has to be six feet long, eight is some jurisdiction, and driven into moist soil.

There is no particular residencial code for antenna grounds, that I am aware of (Being retired I am not up on the current code, there may have been some changes in this area). There are some commercial codes for broadcast antennas.
 
Some (hopefully) helpful hints on grounding rods..

Longer is better...
8ft might not be nescessary, but it usually helps.
Gets you to the water-table or closer at least.
More moisture the deeper you go.

You can make a starter hole, at least a few feet deep
with a "fence post digger" available at Home Depot and
the like.
It'll give you a hole a few inches in diameter, as deep as
you care to struggle with it.
Lot easier to drive the rod deeper with that hole to start
you out.

Pick up a sack of "Bentonite" while at the depot.
Its a type of clay (also used in "kitty litter") to surround
the rod in the larger diameter hole.

Even just 2 or 3 feet-deep of it surrounding the rod
for a total of 3-5 inches really helps to establish the
ground.
Especially when there's no rain for a while....

Spraying on "Plasti-Kote" plastic spray, onto the portion
of the rod/connector fends off the corosion well.
but MAKE SURE you spray it on ONLY AFTER making the
connection!

Hope someone finds that helpful!
Assuming anyone reads the thread anymore. :-)
 
Oh yeah... forgot..

Setting a garden hose on medium-slow dribble right over
where you're gonna make the hole for about an hour
before starting REALLY makes the job easier.

Also a good idea to repeat this AFTER the rod is in the
ground, every 6 months or once a year.
 
Geeze... my brain is in disfunction tonight..
The one time I don't preview my posts I screw em all up..
Lol...

To clairfy:
Thats "for a total of 3-5 inches" diameter hole
and:
"Spraying on "Plasti-Kote" plastic spray, onto the portion
of the rod/connector" that remains exposed.

Sorry!!
 
My son told me that when he was in Signal Corps they had a lot of difficulty getting a good ground out at White Sands... duh, sand is glass... and that is an insulator! They would have a water truck back up and dump a load where they had the ground rod driven.

Then they had a electrical ground. :D
 
The electrical power system needs a ground rod per Code for life safety. This has to be 6 to 8 feet depending on local conditions. Here in California with our long, dry summers, 8 foot is my local requirement.

My antenna has a ground for the coax shield to reduce electrostatic interference. That makes for a quieter signal. I put in a 4 footer since we're not talking high currents.

The third case is lightning protection for the antenna. This is much more serious where lightning is a problem as it has to handle high currents. A strike can vaporize the conductor and usual advice is keep this system on the exterior of the house and to avoid sharp bends as the current might find an alternate path to ground.

Practice for electrical generating plants is to have three ground systems - a grid for the power electrical system, another for internal low voltage power, and a third for instruments.
 
The bentonite would help in both those cases...

Very interesting!
Both the White Sands anecdote and the power station
grounding scheme.

Whitehall...
Do you find that the shield ground causes ground loop
problems with your system??
Assuming your system has at least one 3 pronged plug,
that is....

__________________________

Hmm... I hadn't thought of "dumping a load" where the ground
rod is driven..
I wonder if that would help...................
 
The NEC says 8 feet for service ground.The AHJ may allow 6 feet in moutainous areas where you can't get 8 feet in the ground.
You really need to tie all ground rods together if possible as they will act like an anode and cathode with a lightning strike.Whatever is between them is in trouble as I found out the hard way.
 
Yeah, but that is for an electrical system. We are talking about grounding an antenna, not house wiring. Do you really think that a lightning bolt can tell the difference between a 4' rod, 6', or an 8' rod? Do you think it would make a bit of difference in a lightning strike?

I don't.

I've seen what happens when lightning strikes power poles, trees or other objects. I don't care how big the ground wire is, it is now vaporized and whatever the lightning hits is severely damaged. A ground rod and wire is not going to "save" your stereo gear. The most you can hope for is just to keep static down.

Lightning is going to hit where it wants to.
 
Paul,I am not talking about saving your stereo gear.I am talking about saving your life.

I had a bolt blow a hole through a cinder block wall to get to a rod I had driven in my basement floor as an RF ground for Ham radio equipment.A friend who spent his career as an engineer studying lightning protection for a fortune 500 company said that from all information it would follow the path of a #8 or larger copper wire.It definitely won't carry the energy but it will establish the path according to him.

He also says that if you have two ground rods in close proximity in a lightning strike that you could have as much as 100 million volts step potential difference between the two.

Would you rather it take a random path through your living room or give it an easy no resistance path?

Why do you think it went to my ground rod to begin with?Why do you think it followed some 22 guage rotor control wire and burnt a hole in a transceiver?It follows the path of least resistance.

No more trouble than it is,is simpler just to tie them together than wasting a lot of energy trying to argue about whether or not there is any need.

Also,there are many in the ham community with towers who think you are better off not grounding anything.Maybe so. But,if you do so with multiple ground points around your house,tie them together.
 
Right, but I don't think it would make a bit of difference if the rod were 4' or 8', at least not to the lightning. :scratch2:

But I could be wrong. :dunno:

:D
 
I think we are talking about two different things.

The service ground rod being at least 8 feet is so that if for some reason your house loses the neutral,the rod will carry a lot of the voltage of a short to ground.It's a redundant safety thing.You would still have a lot of weird voltages all over the place ,because the ground rod can in no way complete the circuit for a house,but you shoudn't get electrocuted.
 
Well, guys have been talking about "code" specs for ground rods. What I am saying is that applies to electrical system ground rods, but I don't think there is any "code" for antennas.
 
OvenMaster said:
:yikes: Are you kidding me?? If that's the case, then I'm down like a minimum of 36dB from antenna to input!
Tom
Click to expand...

Coax cable also has losses. Generally speaking, the thinner coax cables tend to have higher loss per 100 ft, and heavier cable has less loss. RG59 will have about 3dB loss at 100MHz (the FM band) over a 100 foot length. RG6 would have about 1.6dB loss. So use the heavier coax, and use the shortest practical path for teh coax cable. And also pick a reasonable spot for the antenna, higher up usually improves signal strength. Mount it at least 5 to ten feet from any other antenna, or metal objects other than the mast. Things like gutters and metal roofing flashing can degrade the performance of the antenna. Oh, and avoid chinnmeys, as soot and such from the furnance or fireplace can slowly coat the antenna lead in wire and insulation of the antenna, also degrading reception.

Twin lead, when clean and dry, has lower losses, but nearby metal objects (like a few inches away or closer) will degrade its performance.
 
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