33' Verticals - Why they Work and Why they Don't!

[@hennero.3826]

Thank you for sharing your profound knowledge with us. 🙂

[@hamradioguys]

Thanks very much, I am glad you like the videos. The community with many extras will be live and online soon.

[@donalfinn4205]

Great video! I bought a 33’ vertical from InnovAntennas and I am very pleased with it. It is super strong and handles the mad winds we get at my qth and doesn’t need guying. Subbed.

[@hamradioguys]

That's Great to hear Donal. I used a software mechanical optimiser to achieve the taper schedule on that antenna and the larger equivalents the Vertigo V43 and Vertigo V66. needing guy guying helps when garden lots are very small too and less to trip over!

[@donalfinn4205]

@@hamradioguys I honestly think that this 33 foot vertical is the only vertical that would stand up to the sudden gusts that we get here. Even after twenty years, I am still surprised by their intensity. I knew it was solid when I went to assemble it. Well done. No worries at all. EI3KY

[@billwilliams5965]

Thank You for the Info... I feel like a 71 year old student... Excellent information, so please keep it coming

[@hamradioguys]

Thanks so much Bill, great to receive such positive feedback

[@thegingaman]

Great presentation!

[@hamradioguys]

Thanks very much, appreciated

[@RT1Q_Andy]

Thank you, 73!

[@hamradioguys]

You are welcome!

[@geoffvk3sq113]

Great video, I learnt a lot.Thanks. PS how can I download your video

[@hamradioguys]

need to subscribe to KZbin premium, this allows download.

[@Ei2iP]

Super Justin, very informative

[@hamradioguys]

Thank you

[@chrisharris5327]

Would like to see the same comparison for the 43 ft vertical 80m thru 20m. Thanks for sharing your knowledge!

[@hamradioguys]

This I will be doing and for the 66' vertical too

[@timsmith1668]

Great presentation Justin. Two things.. 1. Can you elaborate on the 8 ground radials (or more) and the min length these radials could be for this 33'V to still operate effectively. Most of us UK operators have postage size gardens and this would be good info to know. 2. Can you add a link in the more section of your video where we can learn how to build the 400 ohm RF choke for this antenna please.

[@trippnology]

Short answer: 8 x 1/8 wave radials will perform better than 4 x 1/4 wave radials, as most of the current is at the feedpoint end anyway. Also, laying them directly on the ground will detune them slightly, so it's not critical for them to be an exact length. Exact length (tuned) radials are only required for an elevated 1/4 wave GP antenna. Long answer: Radial System Design And Efficiency In HF Verticals by Rudy Severns N6LF

[@hamradioguys]

Hi Tim, 1/4wl for the frequencies you wish to use. if you cant' get a 1/4wl, feed impedance/SWR may not be so good and nor radiating efficiency. I will do a separate video on making an RF choke to suit.

[@timdbl7804]

Thanks again, Justin, for revealing some of the facts of which i guess many folk were oblivious. A constructive comment re the high-angle performance on 18 MHz: I think it very rare that ionospheric propagation would happen above about 30 degrees elevation, at this frequency..... I must do the propagation calcs, when I get a few minutes, and get a more accurate assessment! 73, Tim

[@hamradioguys]

Thanks Tim, This is in fact my point - anything high angle is largely lost, those lobes are not just transmitting into space - you are receiving from those same directions too.

[@timdbl7804]

@@hamradioguys Yep; I'd like to estimate how much extra cosmic noise might come in at those high-angles and compromise receive signal-to-noise.....

[@justmejonboy]

Really interesting factual video that explains a bit of what's happening, different to other 1/4 wave youtube channels. If I understand correct (and I have read all the comments and replies), the vertical part of the antenna connects direct to the centre of the coax and the outer on the coax connects direct to the radials, the earth stake is then connected to the radials centre point via the 9uH inductor, 400 ohms at chosen freq is enough to prevent wanted RF to head to ground, the unwanted RF (eg 300khz from a SMPSU would see around 17 ohms to ground and take that route. I presume you could also use a balun to limit common mode currents as well as the 9uH ?

[@hamradioguys]

Yes correct and so too with a balun. Ferrie current balun at each end of the coax ( antenna and radio side) is the best option for lowest noise

[@justmejonboy]

@@hamradioguys thank you

[@seanmckay204]

Would love to learn how to "tune" or adjust the take off angle!

[@stanholmes4293]

Thanks again. Learnt from each video. I have been looking at the rybakov antenna 7.6M wit 4:1 transformer. This seems to have a lower radiation pattern except for 10M band. What are your thoughts on this antenna? Would be good to see how you can improve radiation angle of the 33ft in a video

[@hamradioguys]

Thanks for the comments. I am not aware of the antenna in terms of modelling it. 4:1 transformer at the based and for want of a better description an apparent 'inverted 'L' albeit with a sorter top section. ground conductivity will affect radiation angle the most. the patter of this antenna is likely to be slightly directional and therefore, angle of radiation would vary upon direction. I will model it and give it a go and report the findings.

[@hennero.3826]

Thank you for sharing this comparion of the two antenna layouts. 🙂 As I am not a native English speaker and I also still consider myself a ham radio newbie, I might not have understood everything correctly and maybe I am not drawing the right conclusion. However, what I think I can conclude is this: When looking for monoband antennas for 20m and 17m to make DX contacts, it seems to me a vertical λ/2 dipole is the better choice and for this purpose (DX) there will be no advantage in terms of lower takeoff angle and gain when using a (shorter) vertical with a number of radials instead. Did I get that right? 🤔 73 de DL1HNR, Henner

[@hamradioguys]

Thanks for the comments. the vertical center fed dipole is not practical mechanically speaking. the comparison what to show the relatively comparable performance between the two and how to correctly install and setup a vertical with radials

[@hennero.3826]

​@@hamradioguys I see. Then let me put it this way: If - especially for the bands I mentioned (17m, 20m) - I have an easy means to set up a vertical dipole, for example on a 12m (40ft) GFK pole, and I therefore do not need to reduce the antenna's height/size, then with the vertical dipole I have more or less the most efficient wire antenna for DX QSOs. However, if - for whatever reasons - one needs to go for a mechanically more practical antenna, then the shorter vertical with a sufficient number of radials is an alternative with nearly the same performance. (I assume that most native speakers correctly understood what you were trying to show, but I needed a little more help to understand the meaning).

[@hamradioguys]

@@hennero.3826 the best option by far is a horizontal dipole. More practical and exceptionally better in gain as a result of ground gain which verticals to not benefit from. I will be covering horizontal dipoles in a future video.

[@dan_in_sd]

​@@hamradioguys Great video, and to add to your next video on horizontal dipoles. please compare heights as there is some controversy on weather 0.6 x λ is actually better the 0.5 x λ . ;) I have been using 4NEC2 on my linux laptop under Wine. It pretty good. EZNEC4 seems good too.

[@FFdo.]

will a regular rf choke with a ft-240-43 and the shield going to the radials and ground work? or thr design needs to be different?

[@hamradioguys]

The choke would ideally need to be around 9 µΩ (microhenries) to provide the choking at the frequencies you need. simple calculators are available for this. in fact, I may produce on to add into the community area.

[@stewartbaker2752]

Great video. However, an ATU (wherever placed) does NOT tune an antenna - it matches it...

[@hamradioguys]

You're absolutely right-I should clarify what I meant. The ATU doesn’t physically alter the antenna’s characteristics or make it resonant on a given frequency. Instead, it modifies the load the transmitter sees, providing a more suitable impedance match for the PA stage. In other words, while I used the term 'tune,' I was referring to how the ATU adjusts conditions at the feed point, not the antenna itself

[@fm71450]

Thank you for this video. May I inquire about the length of the radials in the diagram? I plan to build a similar wire antenna, 8 radials, but the length of the radials seems to be argued: some say the length is of no importance; others say the length should be uniform and 1/4 wave length; and, others say have radials of varying lengths. Any guidance would be most appreciated. Yours, KQ4IXD

[@hamradioguys]

Hi, I had mentioned (although late on in the video) all radials where 33' the same as the vertical section. if there are a mixture of radials for each band you will use, these will naturally illuminate more brightly on their resonant band. Any multibander is a compromise. if you were going to install the vertical for primary use on two bands, have 4 radials at around 14/wl on each band to ensure uniformity. if you have one for each band, you would induce slight directivity in the direction of the radial of 1/4wl.

[@larrypicard5969]

If I undstood you correctly, A ground stake or grounding system should have an RF impeandance between it and the shield connection. This could be achieved with a relaiively random coil. However, what about using ferrite beads, keeping the length of wire shorter than what will be needed for a wound coil?

[@hamradioguys]

A couple of questions there. Yes, an RF choke (coil) will prevent leakage to ground and keep current in the radials. However, it is not a random sizes coil. for the 400 Ohm reactive impedance required in the EZNEC tool, you will need around 9 µΩ inductance. it is worth investing in a measurement device like the one I showed of in the video. You can use Ferrite, there are not huge currents and this will keep the whole thing relatively small and compact.

[@donalfinn4205]

Great video! I bought a 33 foot vertical from Innovate Antennas and I am very pleased with it. It is unguyed and super strong. Subbed.

[@ZzedZed]

17m is not 17--m.

[@frankjensen5127]

great stuff as usual keep it up i'll keep watching Frank g1hqq

[@hamradioguys]

Thanks Frank and hope you are good