Homebrew dual band vertical dipole for 2m & 70cm

NOTE: Comparative testing of this antenna against one without the "choke" showed that the choke is NOT needed.

Homemade vertical dipole for HAM 2 meter and 70 cm bands. With 1 watt, it will reliably hit a repeater 29 miles away (furthest repeater not blocked by terrain).

The Elmer that checked this antenna for me said "don't touch it, put it up".

SWR across the 2 meter band is 1.1 to 1.4 with most of the band covered at 1.2 or below and 1.1 or less from 146.0 up.

SWR on 70 cm (420-450 mhz) is 1.7 or less through 433.5, 435.5 through 441.5, and 445 through the top of the band. 435 to 435 tops at 1.9 and 442 to 445.5 tops at 2.2.

This is with ZERO tuning done, just tested as built and then deployed. I hope to make another set of elements and tune them for better 70cm performance.

The lengths, measured from the outside of the bottom bend, are:
6 1/4" for the 70cm side
18 5/8" for the 2m side

[polishpicl]

Stowing the elements in the handle is marvelous!!!!

[johnpeterson]

Beautifully made. Thanks for posting .

[izzzzzz]

Also could this design be used in a Yagi, turn the elements in the other direction and add parasitic directors down the length of the pvc, you could drill holes in the pvc and slide the parasitic elements into them.

[CarlosFelipeRequiao]

Very Nice video! Do you think it's possible to add a 3rd band, 220Mhz or maybe change 144 or 440 with 220?
73 de PY5CL

[izzzzzz]

I'm going to try to build one of these for 900Mhz and 2100Mhz into a yagi by modifying an old tv antenna

[TheJkilla]

use 5 inch pipe with 4-5 turns, should fix getting 1 thousand feet of RG58, also suggest using RG8X much better.

[jkbish]

Your chickens keep trying to make a photo bomb.

[Tirufam]

I couldn't find a stainless steel or even an aluminum... would it okay for a copper brass?

[anothergoogleuser]

Interesting design, I like it! I have been watching some YouTube videos on several designs and I like this one a lot. Seems like there could be a lot of different versions for this design. You definitely get the mind thinking and I have a couple of questions for you :-)

What is the spacing for the top and bottom element on the "T"?

The idea of the choke is interesting, I have not seem one on a VHF antenna before. I'm kinda new to antenna design so can you please explain to me the desired effect for this?

[marinmarin]

I made the power first by the UHF antenna. The opposite is yours. And UHF is great. 1.1 whole UHF. Only about 470MHz SWR is 1.45. VHF is worse than me. 1.65 is 144MHZ up to 156 MHz. Over 160MHz SWR is 2.8. Very strange because the bars are long 44cm. The calculator says this is 163MHz. A at 163MHz SWR is 2.8. The best SWR is at 138MHZ. Very strange. Because the barrel for that frequency should be 51.7 cm. And with me 44cm.

I used 4 rods. Two of 16 cm and two of 44 cm. And a parallel connection.

[izzzzzz]

Do you think the length of the bolts might act as a high frequency antenna? Perhaps it would be better to use shorter bolts?

[w.rustylane]

Is that an EGA on yer hat? Are you a Jarhead? USMC 1969 ti 1973; Vietnam '71 to '72. As soon as I get my Tech license I'll probably try making one of these but out of copper instead of stainless. Ohhh Rahhh, Semper Fi, Marine.

[funnyfarmdad]

Is this antenna to be used by an HT unit or would it work on a mobile radio being used as a base station. I like this design but I want to use it with my Yaesu 7900. Also could this work mounted it the attic of my garage?

[Bazzawombat]

18 ft rg 58? way too much, at least 3db attenuation on 70cm, 6-10 turns max.

[lentomies]

Is there a specific scientific cal calculation as to how far apart the 2 meter and 70 cm radiators must be from each other?

[marinmarin]

Does such antennas have better UHF reception because the antenna is larger. Because it includes VHF dipole? Or does it not affect UHF reception or may it fail to receive UHF?

[GFO]

What did you conclude on the 18ft choke. I didn’t any videos on your channel

[kaikart]

Protip: just use two or three type 43 ferrite core as choke.

[berettamod]

Could you explain how the element length was determined please?

[marylouiseacebedo]

Why the choke just like wasting money?