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The Vent Pipe "Lightning Rod" Almost Invisible Antenna
 For the 2/440 Meter Bands

Here is a simple and effective almost invisible method of hiding a 2 meter or 440 band 1/4 wave length ground plane antenna in an outdoor setting with stealth up on the roof and it should have a dual purpose of "doubling" as a "lightning rod" just in case the hoa police asks.
It will get your antenna much higher above ground to help you get a better signal out on 2 meters or the 440 ham band. If you use this idea for a very stealthy 1/4 wave length 2 meter ground plane only, it will only be about 19 inches tall! A single band 440 ground plane would be about 6 inches tall! Height is everything and this will help if you can get it built and installed.

The plumbing codes in the U.S. requires that the sewer drain pipes in homes and other buildings be vented to the outside air and require that there is one or more vent pipes up on the roof to vent sewer gas outside. In case you don't already know, the sewer vent pipe on the roof looks similar to the photo below.

2 vent pipes are on the roof pictured above....located in the left middle and right lower part of picture. The large wind turbine in upper part of picture is for attic ventilation.
Photo taken from the ground.

By using one of these vent pipes as an antenna location mounting idea for a 2/440 band ground plane antenna and making it "stealth" in the process, we offer the following as a suggestion or idea for you if you live in a hoa or antenna restricted situation and want to "hide" (go stealth), a 2 or 440 band antenna up on the roof. Even if you are not hampered by the hoa situation, this is a good method of supporting your 2/440 band antenna.

This method will work best and be more safe for YOU during the installation if you live in a single story house, apartment, etc. If your residence is more than a single story, be very careful and get help if needed. Be extremely careful on severely pitched roofs!

If you look very carefully in the mockup photo above, you should see the ground plane antenna mounted on the side of the vent pipe nearest to the upper part of the roof on the "back" side of the vent pipe as viewed from the ground. The copper colored lines represent the actual antenna elements and the black line represents the coaxial cable leading down the roof surface to the transceiver inside the house.

In the next "doctored" photo below you should see what this "may" look like IF you painted the antenna elements, the mounting, and the coax to match almost exactly the background as seen from the ground. You have to look very close to see the antenna elements and the coax. Painting the "antenna system" that is visible from the ground and its mount to match the background of the roof and vent pipe color will be the most difficult part of this idea. Here is where the "stealth" may help in keeping it almost invisible from the ground.

If the roof shingle design has darker horizontal separations between the shingles as in the photos here, try to add "horizontal" paint marks on the vertical and radial elements of the antenna. This may help with blending of the roof pattern to the antenna. Use your own imagination.

This is not an actual installation shown in the photo above but it demonstrates a bit of Windows Paint "magic" in making the coax and the antenna elements become almost invisible.

So how do you build and mount a 2 meter or 440 band ground plane to the vent pipe? See this article for plan ideas for a ground plane antenna and its support. 
Use the formulas provided in it and you will be close with some small bit of tuning required for lowest swr.

The actual mounting will depend on the size of the vent pipe diameter and how YOU want to mount it. There are many options. Use your imagination as required. Keep the mounting as simple as possible to reduce visibility from the ground and from the street if the vent pipe is located on the street side of the roof.

If the selected vent pipe location is more near the peak of the roof as viewed from the street, then it would be best to route the coax over the peak of the roof and then back down to the radio room. However, use the shortest length of coax leading to your 2 radio as possible given your circumstances.

Here is one idea you may want to try for a support for the ground plane:

Photo shows ground plane antenna mounted to end of short length of PVC.
this article for reference on mounting and building the ground plane antenna to a short length of PVC pipe which is then attached to the back side of the vent pipe in our article.

The whole assembly would be mounted to the back side of the vent pipe using whatever method is best for you and your skills. If the vent pipe is metal, DO NOT MOUNT the antenna below it. Tuning problems and "shielding" of your signal will result. Let the vertical radiator extend beyond the top of the pipe. If the vent pipe is PVC, then there is little concern. Stainless steel hose clamps work well to attach the support mount to the pipe or you may wish to mount the antenna on a metal "L" bracket attached with bolts or screws to the top back side of the vent pipe. Don't drop parts down the pipe and don't cover the pipe with anything! It must be open to the sewer piping below for proper venting. Don't defeat its purpose!. The method of mounting the antenna to the pipe is your choice.

Don't let the antenna mounting support stick way above the pipe end. The more that it or any part of the antenna or coax is "visible" the more it won't be "invisible" to the hoa cops from the ground and the harder it will be to paint for a stealthy look.
Remember to route the coax (lowest loss and smallest size diameter) down the roof shingles following either the "vertical" or horizontal pattern of the shingle separations. This is your choice. In many cases following the horizontal pattern may be easier. Then route as needed to the transceiver but attempt to FIRST route it down to the ground to a real "ground rod" of your choice...then from there, bury it if at all possible a short distance to the entry point of the house to the radio room. Doing it this way will help to convince the "hoa police" that it is a real lightning rod that takes lightning to the earth.

The secret in this idea is in the complete hiding of the coax length from antenna to  the ground rod to the radio! Route, bury and paint as needed to blend in well with the roof and wall background color. You might consider some sort of flower trellis on the wall to help hide the coax feed line. You can use the flowers of your choice including artifical.

Of course you need not go directly to a ground rod although this would be a good precaution against real lightning! In all actuality the antenna really does become a real "lightning rod" because it is up in the air but you could just route the coax from the antenna as needed to the radio in whatever manner you choose as long as it is "stealthed" with paint, flowers, etc with the hope that mother nature does not see it when a thunderstorm comes your way and touch it with her electrified finger.

Much of this idea will depend on your situation, your roof composition, vent pipe layout, design and your skills, but where there is a will, there usually is a way! To help prevent prying eyes, installation in the nighttime hours should be highly considered but not as safe.

This idea may not work for you due to many variables but never give up with attempting to operate "stealth" if at all possible if you live in a restricted antenna situation.

If your "antenna" is "discovered" and you are asked by the hoa "police" what that wire "thing" is doing attached to the vent pipe, just play "dumb" and ack like you are thinking, then say something like, "Oh....it is a lightning rod to help prevent lightning from starting a fire and spreading to the neighbors." Hopefully that will convince them.

Don't forget roof climbing safety and don't install any antenna near power lines.....get help if needed .

I hope this article will give you some ideas for locating a 2 meter or 440 band antenna up on your roof and if you have other ideas for the 2/440 bands or even hf that may help others who live in a restricted outdoor antenna situation, please let me know. Send us your high def digital photos taken from ground level with descriptions, etc of your "stealth" installation. The best ones will be considered for publication with this article and full credit to you of course.
73 - Don N4UJW AT hamuniverse.com