The AM Forum

just came back from home depot with a 8ft copper clad 1/2 "ground rod, 2 copper ground rod clamps ( the right ones, not hose clamps) and 15 ft of stranded #6 barecopper which will go thru wall into shack. I'm thinking a big ass buss bar mounted on a central point on the workbench/operating table to break the wire down into a more manageable size to connect to the gear and such.

Anyone have any good ideas on station grounding I havent covered? it's also going to be used to ground my TV antenna which I never hooked the ground up on (#8 aluminum, and I cant change that) nor do I have any actual ground STRAP. the only thing I can get is copper wire and terminal lugs.

what say om's?

My building inspector suggested bonding to both sides of the water meter. So I walked him over to the meter and lifted the 4 #8 s coming through the hole (my buried ground wires. 500 feet of #8). He smiled and said hook them up also. So I have 2 service entrance rods with #4 to the panel and #4 to the water meter. 3/4 inch copper to the street and 500 feet of #8 in the ground terminated in water. Da more the better

If you have a well with iron casing, connect to that.    My ground rod is 6 inches in diameter and 100 ft into the ground.    After a new garage and new electric service was added, the inspector still insisted on having me add a couple of ground rods.
The ground wire from the casing was brought in with the plastic pipe and connected to the copper pipes of the house.

Just make sure you connect that ground rod to the electrical entrance ground rod and any other ground rods (phone, cable TV, etc) with heavy gauge wire.

yeah. I'm gonna have to go back and get some more wire methinks. I dont have enough to run to the service inpoot and inside the garage. That why I got 2 clamps, but damn if I didnt forget to get the extra wire.

weekend wx forecast looks good.

That's because Iron Oxide is a poor conductor, compared to Copper Oxide/Copper Sulfate.

But, I'd still connect to the casing.... seems too good to pass up....

(I've always wanted to use  my well as a "mirror" for a vertical.... but my casing is only 45 feet.... not 'resonant' 1/4 wave anywhere in the ham bands....... well, close for 30meters)

I wonder of you could put a loading coil on it?

Some good info on grounding here.

http://www.amwindow.org/tech/htm/grounding.htm

For a station "Buss Bar" I use a 1/2 "  copper pipe mounted to the wall
with plastic P clamps, behind my workbench shelf. The main ground wire is connected to one end.  For equipment grounds I use #8 pigtails connected to the pipe with 5/8" SS hose clamps. You can run these along the pipe and tighten as needed.

Mike

cool idea Mike!

yeah, thats a good solution. I got the outside ok, and getting it in the wall ok. it's how best to distribute the ground after that central tie point to the #6. Whats a P clamp?

Your local Home Despot should have them in plastic and metal types.

The copper standoffs on the pipe dept would also work

Yep, same basic set up I use, except the pipe is drilled and mounted on stand-off insulators to allow clamps to be easily added and wires/cables to be passed beneath it.

These are handy too:

http://store.electrical-insulators-and-copper-ground-bars.com/ground-bar.html?gclid=CPKn3ceH4o8CFVB1OAodvTYcMg

Solid copper, pre-drilled. Pricey to buy new, but they show up on ebay from time to time. Just snarfled up a 20" model for $10.50.

Strap (strap) is always nice for tying to ground since it provides more skin area, but decent braid like you picked up should work just fine. And #6 is a lot easier to work with. The idea is that the system drains off any charge before capacity becomes and issue.

BTW, not sure how much gear you're looking to hook up, but I'd advise a separate ground strap for each one over that 'daisy-chain' approach some use to save time and wire.

I use that 1" wide copper braid. Everything gets hooked to it. including the ground rod outside of the shack.

yeah, the daisy chain is bad. possible ground loopage. each piece of gear needs it's own pigtail coming right of the bussbar.Me and the wife are going back to the depot tomorrow to get some nice bussbar that will handle a #6 input and output #8 solid to the gear. I have a edsal lighted workbench with a single stack shelf and a older formica/chrome legged table for the gear itself. 220 for the amplifier. I have to get about 15 ft of that ac line.

What are the wire colors on 220 vac 1 phase?

 

Derb,
Go to the area where they sell breaker panels. They sell buss bars for inside panels of different sizes. or just buy some heavy wire and copper clamps.

...copper pipe mounted behind the bench...cheaper than a bus bar...i have ground rods (copper) inside my well. it is a dug well, so no casing. i had to go down there this summer, about 20ft down, and drove in 6- 8' rods....tim...sk..

220 single phase wire
Green or bare +Safety Chassis Gnd
White = neutral
Red one side hot
Black other side hot.

It would be a waste of time.  The rf would penetrate a few feet into the ground at most.  The well casing would make a good ground connection for 60~, but not much good for rf.  Since lightning's characteristics are closer to rf than to DC, the well casing probably would not make a much better lightning ground than a normal 8' rod.  A radial system would make a better rf and lightning ground than a rod driven in the ground, no matter how deep.

Fun...

I'v learnt a coupla things over the years.   

Had a 12v car battery on a floating dock hooked to a windmill.  Took those 12 volts about 2 weeks to turn a #10 romex conductor on the POSITIVE SIDE to green paste...  (the neg wire was fine)

Had a piece of sheet steel bulkhead that went down 20 feet or so as a ground for a vertical.  There was about a half volt or so of positive DC potential from the assorted copper ground rods tied to my station and hence to the steel via the coax shield.  That 1/4 inch thick steel was corroded clean through in two years.

Lesson learned, watch out for galvanic action.  I tie my AC line/plumbing and CATV copper rod type grounds  to the MFJ artificial ground, which has a series capacitor that isolates it from my equipment/antenna.  DC grounding for that is via a galvanized pipe, which, being zinc, is like a sacrificial zinc on a boat.   That half volt difference keeps my aluminum magnetic loop nice and shiny.   

The MFJs RF ground current was doubled by tying in  a connection to the shield of 100' of coax lying on the ground, presumably acting as a capacitive counterpoise.  (for 160, the MFJ needs an extra few hundred PF, incidentally)

well, I pounded the new 8 ft rod down in today. Putting in new clamps and screws on the 2 existing 10 footers tomorrow, tying them together and back to the service ground and into the shack. Should be done tomorrow. Rods are about 2 ft apart.

wonder if adding a tuned counterpoise to this stapled up to the house would be worth it? Anyone have any experience with this?

I had a MFJ artificial ground to a single 8' copper rod tuned for max current.  Adding a 100' length of coax laying on the ground as a capacitively coupled counterpoise  with both ends of the shield tied to the ground rod doubled the current thruogh the MFJ on 160 meters.   

This effect may have been due to induced antenna currents, so no conclusion can really be drawn.   It would be interesting to research counterpoise performance, to find the optimum height.   Capacitive reactance increases with height as capacitance declines, while losses due to circulating earth currents  decline. 

Experience with mobile operation on 75 meters indicates that a car sized counterpoise works well.  It ought to have a resistance somewhere in the mid single digits, according to Charlie, maker of the Hi-Q line of tunable mobile antennas.

Derb, ifn ur running a dipole, or the like, don't waste ur time and money on it a "counterpoise".

no, I was just wondering if I would get more current moving at RF freqs with a tuned wire off the grounding system. I don't have much experience with anything else. I would assume it's very frequency dependent, with decreasing freq showing more advantage.

Bud, I'm running a 450 ohm ladder line deal tuned with a flashbox. On 75 meters I'm thinking it would be a waste of time. On 160 less so. On lower end of am bcl band, with a vertical, not at all.

Sooo, Mr DERB
Are we to ASSume that you will have a maul on the air before the end of THIS radio season?? Is it one of those Henry amps you have??? Lettuce know when the big day happens.
Will you be using a Heil microphonium?
Phred