Stacked-J - Double High J-Pole
Also known as the Stacked Copper Cactus.
The Stacked-J is a very worthy antenna to consider!
Many repeater clubs have found it to be superior to their retired antenna system.
Although not mentioned in the Authors original article below, he also designed a stainless spring steel mobile version that was produced by a well recognized antenna manufacturer for many years.
A unique and powerful twist to the ever popular J-Pole
Simply because the Stacked-J is so easy to build, I will keep the directions as brief as possible. Although the hand drawn sketch is very rough, it allows you to see what the assembled unit looks like. If you click on this link it will open the image shown on the right, so you can view it more easily.
The First Step is to build a regular MonoBand J-Pole from the Copper Cactus plans for a 2-meter antenna, leaving off the top pipe cap.
Then build a second J-Pole, which will look like an L-Pole this time. The vertical is 38-3/4 inches from the top of the antenna, down to the centerline of the horizontal member. This particular horizontal member mentioned will be the Top member of the lateral stub.
The lower leg of the L consists of two horizontal pipes spaced as close together as you can get them using standard 90 degree elbows.
From the centerline of the vertical, to the centerline of the outer fittings at the end of the horizontal members the distance is 18 inches for 2-meters.
I have not calculated the exact measurements for any antenna design other than the 2-meter band.
A final 90 degree elbow is placed directly under the vertical section and is soldered to the top of the existing J-Pole.
The finished product resembles an L on top of a J, of course the lower leg of the L is two pieces of horizontally positioned pipe.
I hope you can visualize this. As soon as I get the time, I will try to make a new posting with a drawing included.
Happy Building - This really is a GREAT antenna!
73+ de Gary - KGØZP