When I installed the TA-53-M for the first time, I followed the instructions of Mosley for the current balun construction. This was simply winding 12 turns of the feeder coax (RG-213) on a 12.5 cm diameter platic tube. This balun type is generally called the Ugly balun. This "balun" I fixed to the boom of the antenna with two 50 mm brackets. The benefits of such construction is that you don't need a coax connector between the feedline and the balun. The other end of the balun was connected to the feeding system of the antenna. This situation worked well for about two years. However, I thought of replacing this balun by a type on a toroid ring. However, when searching the internet I found various comments that mosley indicates that it would be wrong to install a balun. Nevertheless, I decided to make a good high power current balun and give it a try.

I used a FT240-43 toroid ring and 8 turns of RG-303 coax. This coax is small and is easy to apply on the ring but still capable of handling high power. The balun is mounted in an box of ABS, which is strong water tight. I fixed this box with a bolt M4 to the boom clamp, right under the feeding system. This resulted in very short connection between the feeding system and the balun. I also replaced the RG-213 feeder by Aircell 7 type cable.

Everything is now up and running satisfactory.

View the embedded image gallery online at:
http://dx.to/projects/ta-53-m-balun#sigProGalleriac69a891b22

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