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I just passed both my Technician and General Class license this past weekend, and am now contemplating my first station. To get my feet wet I'm planning on getting a Yaesu FT-7900R Dual band Radio with a yet to be named power supply (probably a Samlex SEC 1223). I plan on installing a DBJ-1 from Ed Fong. He has stated to me:

The antenna is DC grounded so no lighting arrestor is needed. All you need to do is to make sure the shield is grounded (which I assume it is from the power supply). Nothing will protector your antenna from a lightning strike. So yes, if you see a storm coming it would be advised that you disconnect the antenna from you radio. All a lightning arrestor does is to DC ground the antenna which protects your radio with high voltage spikes induced by the lighting. Our antenna is a DC ground antenna so it already does that.

I plan to operate in this manner for about 6 months or so until I can get my first HF rig. I am setting up my "shack" in a bedroom on the west wall of my house where there is a window and an input for my Fios TV cable comes in from the outside there also. I want to make sure that my station is properly grounded for the current configuration but also for my future expansion.

Outside the wall, there's about 8' to the neighbor's wooden fence, and a fairly big tree on the other side. So I won't be able to just go straight up to the roof with my antenna. I live in North Texas, in the Northwest part of Dallas County, so during the April-May time of year we do get our share of severe thunderstorms with lightning and hail, though in 30 years we've never taken a hit around our area.

What would you suggest that I do to begin a good grounding system? I do have a computer that I'll be using, the power supply, the FT-7900R and that's pretty much it. I have a surge protector that's plugged into my home 3-wire socket.

I have SOME room outside, but not all that much but I COULD drive copper rods close to the house if need be. I've ready all about these very elaborate grounding systems, and I'm honestly not sure I have the room for all those things at my house!

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  • $\begingroup$ Your question has a number of incorrect ideas in it with regard to arrestors and lightning. Ed Fong is just plain wrong. $\endgroup$ – David Hoelzer May 18 '16 at 10:55
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That statement is wrong on several levels.

The antenna is DC grounded so no lighting arrestor is needed.

A lightning arrester is needed, even if the antenna is DC ground. The arrester's job is to limit the center conductor's voltage to be not very different from the shield. That the antenna is "DC grounded" isn't worth much. Lightning is not DC.

In fact, the fact that this antenna works tells us that it's not grounded at high frequencies. The fast pulse that is lightning also has high frequency components, so from the perspective of the lightning, the antenna is in fact not grounded.

All you need to do is to make sure the shield is grounded (which I assume it is from the power supply).

Simply attaching the shield to something else that's grounded in some way isn't going to help at all. Lightning is a very fast pulse, and as such we have to think about it as RF, not DC. A circuitous route to ground is worth very little since the inductance will encourage the lightning current to flow elsewhere.

Nothing will protector your antenna from a lightning strike. So yes, if you see a storm coming it would be advised that you disconnect the antenna from you radio.

Tell that to professional broadcast stations. I'm sure whenever there's a storm, someone goes up the mountain to disconnect the antenna while the station is off air for several hours, right?

All a lightning arrestor does is to DC ground the antenna which protects your radio with high voltage spikes induced by the lighting. Our antenna is a DC ground antenna so it already does that.

That's not what they do. Most lightning arresters have a spark gap between the shield and the center conductor. When the center conductor gets too high, the gap sparks, limiting the voltage between the shield and center conductor.

Some are DC grounded, which can be good since it prevents static buildup on the antenna. Some are not DC grounded, which is important if the feedline is powering remote equipment with a DC bias. If you look at lightning protection produces from PolyPhaser for example, they have both "DC block" and "DC pass" products.


If you want to protect your station from lightning, see How can I protect equipment against a lightning strike?

And if you don't care that much about lightning protection, don't worry about grounding. A ground isn't necessary for a radio to work. Just disconnect the antenna in a storm, and if you are using a vertical, be sure it has radials to provide a "ground" plane.

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and welcome to ham.stackexchange.com! I can't say that I agree with Mr Fong, because a good lightning arrestor also includes components to block the high voltages resulting from a nearby lightning strike.

Perfect protection against a direct lightning hit is probably not possible at your house, but nearby lightning strikes can also do damage, and that's something that you can do something about. Lightning protection is a compromise, and each ham must decide for him or herself how much is desirable and affordable. If you asked ten hams what the best compromise is, then you'd probably get ten different answers.

In my opinion, a good compromise to start with would be to use a good-quality lightning arrestor mounted on the end of a ground rod. The ground rod should be buried in the ground of course, and also connected to your existing electrical ground rod(s) according to code. Installing a lightning arrestor would mean that you would need to cut pieces of coax to size and install connectors on the ends, which can be a bit tricky for a beginner; you might want to go to a meeting of your local ham club and ask for some help there.

You might also want to think about insurance; it wouldn't be a bad idea to ask your insurance agent whether your homeowner's or renter's insurance policy would cover lightning damage. If not, you could buy coverage for your equipment from the ARRL.

Good luck, and have fun!

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I think what I have decided to do for the outdoor grounding station is to start with a single copper ground rod (specifically an ERICO 8' .358dia) driven into the ground just outside my "shack". I'm opting for a Alpha-Delta UCGC that will be put on the rod along with an MFJ-270 lightening arrester. I intend to run a 6ga copper wire from the rod to my meter ground.

From what I can gather, I'll then just use RG8X Coax to run from the antenna to the arrester, then another coax inside to my FT-7900R. The Power Supply will have it's own ground wire (not sure what I need there) to go to the grounding station UCGC. I don't know whether I also need a ground from the receiver to the ground rod.

Inside, I'll have a surge protector with battery-backup plugged into the wall AC, with all equipment plugged there. Then if a particularly severe storm comes along I can simply pull the antenna on the unit, and pull the surge protector from the wall.

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    $\begingroup$ If you connect any part of your station to the copper rod outside your shack and you don't disconnect that in a storm, you are pretty much guaranteed lightning damage when the voltage gradient between your shack grounding rod and your electrical service ground tries to resolve itself by driving current through your equipment. Ground in exactly one place, which probably means through the power cable, by plugging it in normally. $\endgroup$ – Phil Frost - W8II May 17 '16 at 19:39
  • $\begingroup$ Just FYI: this is not a discussion forum — you should avoid asking followup questions in the “post answer” box. In this particular case, you're in fact proposing an answer to your original question, and responses to it are criticism of the answer, so it works out mostly OK, but I've edited your answer so it's not asking questions. If you think you need more information in answers, edit your question; if you've thought of another question because of this one, post it separately. $\endgroup$ – Kevin Reid AG6YO May 17 '16 at 20:26
  • $\begingroup$ You absolutely want to connect your station and the antenna to a common ground. $\endgroup$ – David Hoelzer May 18 '16 at 10:57
  • $\begingroup$ From my answer, addressing the connection between devices: have a single solid ground that you can use for your whole station. A copper pipe with hose clamps could work or a large copper screw-down grounding point. $\endgroup$ – user2943160 Jun 6 '16 at 0:47
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A few notes on top of the other answers: a few feet of copper/copper-clad-steel to make a ground post is a good idea, a copper or tinned braid into the house from the post is (at HF) a conductor to ground, and a single ground point for your station (I've seen a copper pipe used on the back of a ham station's bench) to strap your rig/DC supplies/lighting arrestors to rounds out grounding. Make sure that you have secure connections between each. A screw clamp with multiple bolts outside and some good pipe clamps inside should ensure you've got a good connection. Definitely inspect the outside connection every couple months.

For some NEC-based advice on conforming to safety standards for antenna installation, this document is a good resource (also available in the Internet Archive Wayback Machine).

To protect against lightning/static discharge when you're away from your station, a coax switch to choose between your antenna with lighting arrestor and an inside dummy load/cantenna would make disconnect easy. This also makes it more difficult to inadvertently transmit from your station, provided you remember to change from antenna to load at the end of each session. Remember to choose a load that has a short-time rating for your usual transmitter (or amplifier) output power setting and frequency.

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Lived in this house for over 30 years and never experienced a lightning hit at my house and I have a 50ft mast with an old C-Band antenna outside.

After talking to local hams in my area, I'm just going to rely on my regular three-prong ground in my house with a GFI socket. I will have a pass through panel on my window that hooks up the two outside antennas (UHF/VHF and HF loop) to the rig inside. In case of storms, I simply disconnect all inside connections at the window pane. The loop is going to run under the eaves of my house not 60 ft in the air, so no danger of lightning there. The UHF/VHF antenna will extend a mere 5ft over the roof, and I will run a ground to the meter for it.

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  • $\begingroup$ Hi, it looks like you accidentally created two accounts, as you're not showing up as the author of the question. If you like you can have them merged. $\endgroup$ – Kevin Reid AG6YO Jun 7 '16 at 16:53

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