Converting the BITX40 to 20M

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20M Inverted V with Lightweight Dipole Center

One of the many joys of being a ham radio operator is building antennas. I’ve covered the L-Match tuner and long wire antenna in the past, and while it’s a great way to get on the air, a resonant antenna is always nice- if you have the room for it. When you’ve only got 5w of power to play with, efficiency matters, and sot it’s good to try out different antennas to see what works best for you.

Since I converted my BITX40 to 20 meters, it has opened up new possibilities. I now have the ability to build resonant antennas that were a bit too big before. An Inverted V dipole is only about 16 feet per side, easily small enough for my back yard.

I borrowed the 23′ antenna pole from my long wire, and erected an 20m inverted V using some zip ties and an camera tripod. I started out with just a basic BNC panel connector on a plastic card, and when it started raining, it started failing! I devised a new center center that you see in the pictures below, with hot glue for weather protection. Hopefully it can live up to the Pacific NorthWet winter!

You’ll notice that in one of the pictures there is a jug of water hanging from the center of the tripod to weigh the whole thing down when the wind picks up. I was going to install it more permanently at a later date, but this stuck- it’s held up for a few years now.

There’s a video about it on YouTube:

The whole antenna, shown with the original dipole center. Fishing line is used, tied directly to the antenna wire for now.
The whole antenna, shown with the original dipole center. Fishing line is used, tied directly to the antenna wire for now.
Removed the broken head from this old tripod, and zip ties to the rescue for this installation.
Removed the broken head from this old tripod, and zip ties to the rescue for this installation.
I wound the RG58 up the antenna, but it can be zip tied too.
I wound the RG58 up the antenna, and zip ties helped out.
This center piece worked great, but is not weather resistant, and with the BNC connectors, his heavy.
This center piece worked great, but is not weather resistant, and with the BNC connectors, his heavy.
No BNC connectors, and tons of hot glue, no strain relief needed.
No BNC connectors, and tons of hot glue, no strain relief needed.
The proof is in the pudding. Being heard across the pond in Australia. I’m very happy with the performance of the antenna!

1 comment

1 ping

    • Arthur Bryant on August 13, 2017 at 11:15 AM
    • Reply

    Great article Ryan, I ran an inverted V strung in a tree for years.

  1. […] start. I’ve used mine to do everything from building a microphone for my BITX40 to building a dipole center that is weatherproof even in heavy […]

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