OpenTube

Simple 20m Vertical Antenna With No Radials - DX Contacts on a Flat Band

Shack & Field - G0CNN

19,259 views

Join me as I make a very simple, yet effective antenna for the 20m amateur band made entirely of RG-58 coax and it doesn't use radials, so a bonus if you haven't got the space to lay any out on the ground. There is an air-wound or ferrite choke option to this design.

Having had success with the same antenna on 15m (21MHz), I scaled-up the design for 20m amateur band. This video shows a step-by-step simple build process, analyser tests and then on-air real world testing with some successful DX contacts on what was a very flat band.

The 15m Build & Test video can be seen here: 15m Vertical Antenna Simple Build

This is one of many ham/amateur radio related videos on my channel, which is all about simple practical projects and operating, both in the shack and out portable & mobile. If you like what you see, please give it a like 👍🏻 and subscribe to the channel if you're not already, and remember to hit the bell 🔔 so you’re notified of new videos as soon as they're published and you don't miss out.

Thank you for watching 🙂

73 Ian

20 Comments

@mewrongwayKOCXF 1 year ago

Awesome antenna Ian!! 👍👍👍

@donkeykebab 1 year ago

Thank for this. Going to have a go myself

@M0RMY 1 year ago

Enjoyed that mate - nice re-brand too.

@M8KHC 1 year ago

Loving the re-brand

@russellbaker7098 1 year ago

I have one of these antennas for 20m on a 12m pole. It's got an air cored choke, handles 500w of digital modes and works really well.

@redjohn20001 1 year ago (edited)

The thing with a t2lt with a ferrite choke is that you can alter the lengths of the top and coax halves, giving a slight offset center fed dipole, improving the match and hence the vswr. Thanks for the video.

@samforbes5270 1 year ago (edited)

Thanks for bringing this design to my attention! I was planning on using a 15m vertical dipole on a 10m spiderbeam for field day later this month. I have made a 15m version of the t2lt and am going to do some wspr tests to accurately compare the 2. Instead of cutting the coax I simply soldered a quarter wave length wire to the center pin of the pl 250. Although with more thought it would be better soldered to an so239 chassis that gets plug into the coax. Im looking forward to making a 20m version for an easy pota antenna and an off centered fed version for multiple bands. Perhaps a non resonant off center fed vertical. 25ft wire with 15ft of radiating coax with the choke at the bottom of a 40ft spiderbeam and a 4:1 unun at the feedpoint. Lots of things to consider. If only I were better at NEC modeling! The radiating shield of the coax trick can be applied to many different kinds of antennas!

@Sailor009 1 year ago

Thank you for the alternative to radials. Given I live in a HOA and have little patio area that has patio bricks base. I am always looking for antenna options that do not require long radials. My patio area maximum length is 25 ft. Currently have a delta loop with base center feed on a 6M mast. Will keep watching your site for options. Regards Ed KK7UNA

@batwillow 1 year ago

i made my T2LT 20m antenna as follows... choke was 15 turns on a 110mm diameter, then 5m of the lower part and 5.02m for the top section and I get a reading of 1.18 vswr

@trig6712 1 year ago

Good GM4NNC

@voiceovervandeen 1 year ago

Hi Ian, I experimented with lots of T2LTs during lockdown particularly for 10 & 11m. I found the best way to permanently attach a "single core flex" radiator was by simply adding a cheap PL259 plug onto the RG58 & soldering the flex directly onto the centre pin. You can easily connect quite thick flex using this method. i.e. 6mm sq.
As I wanted the flexibility to switch between different element lengths, thicknesses, straight & spirally wound fold backs etc. I moved onto attaching these experimental radiators to the guts from old SO239 Chassis Mount Sockets (the Round type not square). Doing it this way made it dead easy to swap them out during back to back bandwidth, tune, & OCF testing. 73 M7GVS / 2E0GVS

@johnharrison373 1 year ago

Ian, I'd have joined it at the centre point using a quality heatshrink crimp butt connector. It would have been mechanically sound and waterproof. Then, a piece of glue lined heatshrink over that and the outer sheath.

@zaperfan 1 year ago

Great Job. What are the vertical line across the waterfall so kind of interference?

@gtretroworld 1 year ago

Liking the rebranding Ian, I was tempted to do the same a while back because for some reason radio has overtaken the whole idea behind the channel. 😂

@geirha75 1 year ago

VF rg58 is usually 0.66.

@hennero.3826 1 year ago

Thanks for sharing. 🙂
I like the T2LT antennas. When I started with ham radio last year, a 15m version was my first antenna and it worked great! 🙂 Sometimes I wonder why the T2LTs aren't even more popular.
I have also thought why usually these antennas are presented with an air coil, and I was asking myself why not using a ferrite to choke the lower end - so thanks for confirming that this apparently is even better.
There was one thing I was missing in your video though -
the process of cutting the outer off the outer part of the coax to get such a perfect result! I am always struggling with this and was hoping to see how to do it without damaging the inner insulator/conductor and the fingers. 😉
73 de DL1HNR

@johnwhale2900 1 year ago

Hi Ian. This looks pretty good for my first home brew vertical. I have all the materials needed and plan to have a go at making it this week. However I do have question. If the antenna needs trimming how would you go about it? Take it off the top or a bit off both ends. If its the latter I forsee that you would need unwind and reposition the choke which will be a bit of a pain. What do you suggest?