Cheap and Easy Portable Antenna Mount

(Or Out of the Attic and into the Yard)

By Stephen Reynolds W4CNG

There are several variations of this mount out there commercially produced and homebuilt, but I have not seen an article dealing with how to build the mount alone. This article describes how to roll your own in about 3 hours start to finish. All you need is a hacksaw, drill, screwdriver, wrench and a quick trip to your hardware store. This started as one of those Saturday afternoon whims, a solution to a problem that will appear later this year when I operate on Light House Weekend, solved well in advance.

Parts list is as follows:

How to assemble:

Cut the aluminum flat stock in half, you will have 6 4 ft pieces. On the end of three of the pieces, make a bend 4 inches from the end at a 60 degree angle. (See Picture 1)

Picture 1 Shows disassembled parts and angle of bent end of aluminum stock.

On the other end of the 3 bent end pieces, drill two holes for the hinges. Do the same on one end of the other 3 pieces of flat stock. The three bent end pieces will now have 3 holes drilled thru them. Mark one piece Top, one Middle, one Bottom. The three holes will be drilled thru all three units, two pieces at a time. Mark three holes in the top piece. Drill the top piece with all three holes. Start with a 1/8 inch drill bit for the initial holes, you will drill them out to accommodate the 10x32 screws later. Place the middle piece under the top piece and at an angle of 120 degrees. Mark one of the 3 holes in the top as a pilot hole. Using a marker mark thru the top piece onto the middle piece. Mark the same pilot hole on the middle piece also. Drill the middle three holes. Place the bottom piece under the middle piece and repeat the marking process again, then drill it. When you are done you should be able to assemble the three pieces together and check for hole alignment. If all is close, you will be OK. Next drill all 9 holes with one drill size larger than what is needed for 10x32. (I don't know what size drill as all of my drills are so beat up, they have no markings on them, so I use what fits).

When this step is completed, assemble the three pieces and make sure all three holes line up. If all is ok, add the hinges and end pieces.

See Picture 2 below for details.

Picture 2 Finger tighten the screws and hinges, then close as shown and press to flatten slightly, the hinge will bend a little. Then tighten with screwdriver and pliers.

Following the addition of the hinges, take the top section assembly and using the dual mobile whip adapter (you can see it was a L shape that now has been flattened out, I did say cheap). Mark three holes into the adapter with it placed on top of the top assembly piece. Drill these holes. When completed this is now the Top piece of the antenna mount assembly. If you have one of the SO-239 to 3/8-24 stud adapters you are ahead of the game. When you bend the top piece of the three bent pieces, bend it at 6 inches instead of 4 inches. You will have a 2 inch overhang in which you can drill the required hole to put the SO-239 to 3/8-24 stud adapter. The bracket it came on is now not needed.

See Picture 3 below for the completed assembly.

As you can see this is an intermediate project, requiring a modest amount of shop skills, and up to now, no electronic skills. Take the whole thing outside and assemble. Here is where the wing nuts come in handy. NO tools are required for assembly. This is another plus. This whole thing will fit in a space of no more than 4.5 feet by 5 inches by 3 inches. Very compact, will fit in vehicle trunks easily and most other spaces easily.

Get one of your mobile whips and mount it on the Portable Antenna Mount. Using a MFJ Antenna Bridge, I found that the tuning on 20 meters and up decreased in frequency, so much so that on 15 meters I had to run the whip down into the HamStick. A word of caution, you can only run the whip down a certain distance before you risk damaging the whip. Twenty was still good enough for all the phone band. Forty meters went up a little, and 75 meters was right on.

I also drilled a inch hole in the end of the ground coupling straps about 2 inches from the end. This is a good place to use some railroad nails to hold down the ground coupling devices. Also you need to use some sort of restraining tie down if you put some of the larger whips on it, including screwdrivers and Outbackers. All can be adapted to this ground mounted Portable Antenna Mount. See picture 3 below for fully assembled and deployed unit.

The total cost of this assembly was $65.00. The 3 8 ft aluminum sections cost $21 each with the balance in hardware. I had the dual whip adapter which I traded for some time ago, so I didn't cost it, however they usually go for around $20 at a hamfest, that would run the cost up to about $85 for all new items. The commercial Alpha-Delta version of this is more than 2X the cost here, and I am not sure if it is as easy to assemble as this one is. Disassembled you have what is up in picture 1. Not much for what it does really well.

Have Fun and enjoy this Portable Antenna Mount.