Homebrew 5/8 wave vertical

[ChelseaCat]

Ok Im into my homemade antennas and love the simple dipole which is what I have connected to a roach pole BUT now want to try something different.

I really fancy making a TL2 Antenna, it looks simple and their is no connections other than a PL259 at the radio side Ive read up on this and the reviews sound great.
https://www.youtube.com/watch?v=Gf8xeq77kkI

Here is a twist though, the antenna above is a half wave but after reading all the great things about 5/8 antennas Im wondering if anyone has made one of these TL2 antennas but measured up for 5/8. Is their any point would the gains be worth it over a half wave. How many turns would I need for the choke / 1/1 balun.

As for my dipole it works great but with it being so high up on a fishing pole the coax runs down along side the antenna, dipoles work better if the coax comes of at right angles which is hard to set up on my current creation. When I set the dipole up it had really low VSWR but as it went up higher and the coax started running along side the antenna it got harder to tune it although its not bad its not as good as I would like it to be.

So calling all expert antenna guys should I just stick to the youtbe version half wave antenna or go for the 5/8 wave antenna and can you help. Im going to start in a couple of weeks time.

[Anthony123]

In theory the 5/8 wave does have a small amount of gain over the 1/2 wave.. and it focuses the radiation lower to the ground also, This is due to the extra lenght...The gain from a normal 5/8 wave is anywere from 1.5 dbd to about 3 dbd... Not the 9.9 db ? you read of in marketing hype...Any extra gain is worthwhile no matter how small it is.... If your after gain then the only real antennas for this are Directionals.. such as the yagi, Quad, V beam, Delta deam... etc.. A simple two element yagi can have around 4-5 dbd and a decent enough rejection of the back.. so beaming stateside you block of a lot of Europe..

[ChelseaCat]

Yep a yagi is what I have planned for next year but for convenience and space and ease one of these has to be tried

[thedeerhunter270]

My understanding is - a 5/8 wave is electrically a 3/4 wave, but shortened by inductance to 5/8 to effect the radiation angle. So I guess you could modify the t2lt to make the top section 5/8. Not sure it would be worth it to be honest.

[ChelseaCat]

Im going to give it a go, love experimenting with homebrew antennas

So using the central frequency of 27.500mhz a half wave is 17ft. 0 - 7/32in divide it by 2 to get both sides of a dipole

A 5/8 wave would be 21ft. 3 - 9/32in. again divide it by 2 to get both sides of a dipole

So going by the example in the video I would measure down the coax approx 21ft. 3 - 9/32in and adding an extra 6 inches for tuning.

Then measure up the coax approx 10ft 10inches from the 21ft 9inch mark and remove the braid at that point from the top of the antenna down to the mark.

Now this is where the coil would be or the ugly balun in this case I still think it would be 5 turns on the soil pipe for this.

So thats the plan Im going to give it a go in a couple of weeks if I cant tune it Ill make it as per video into a half wave.

Wish me luck guys

[wa10]

chelseacat,
a 5/8wave tl2 is a gainmaster, you need some form of matching if its not a 1/2wave,
check out the homebrew gainmaster thread.

[ChelseaCat]

Oh right I thought it would just work the same way maybe just making a half wave lol Ill take a look at the difference thanks