Ham Radio: A Look At The 43 Foot Vertical Antenna

[@carlosadrianob.blanco6521]

Thanks for sharing all the information Tim. I´m planning to build one vertical but from the Vertical Antenna book by William Orr and Stuart Cowan. The antenna is 41' (12.5 m) high and built of sections of aluminium tubing. The bottom section is a 20 foot (6.1 m) length of 2 inch (5.2 cm) diameter irrigation pipe. The top 3 sections are made of telescoping sections of tubing, all having a wall thickness of .058 inch (1.47 mm). Diameters of the sections are 1.75 inches (4,45 cm), 1.5 inches (3.81 cm) and 1.375 inches (3.49 cm). It uses 8 radials, 60 feet (18.3 m long) and 8 foot (2.4 m) long ground rod is driven into the earth at the base of the antenna. Credits: Vertical Antennas by William Orr, W6SAI and Stuart Cowan, W2LX. Greetings 73 PY2QA.

[@timg5tm941]

Sounds a great project Carlos!

[@davemaier7]

Tim, your videos are very informative and worthwhile watching. Thank you for all that you do for Ham Radio, David K7CI

[@timg5tm941]

Very welcome David and thank you for stopping by!

[@michaelharkey9675]

Antenna stuff is very interesting. I must say this video has the most amazingly pleasing audio I have ever heard on KZbin!

[@timg5tm941]

Thanks!

[@mike94560]

I use a transformer (no Unun) to make it work on 80 and 160. It works great on 160 that way. I won an ARRL 160m CW contest with it.

[@timg5tm941]

Nice job!

[@dougtaylor7724]

What are you using to get on 160?

[@mike94560]

Normal operation 40-10m is via the standard 4:1 UnUn. For 160-80m I use a big toroid transformer with appropriate taps. I switch my coax over to that box and disconnect Vertical from 4:1 UnUn and connect to transformer. No relays all manual switching. There are 2 pairs of external banana plug jumpers that get shorted to make it tune on 80m.

[@robertbobbitt8448]

put a tuner right at the unun and the unun right at the base dont worry about coax loss its eliminated

[@timg5tm941]

Agree - done that many times

[@DK5ONV]

Tim's gonna make his Mojo working at any time and anywhere. That's how it's supposed to be like.... 💯👍🙋‍♂

[@timg5tm941]

Indeed!!

[@Not_So_Weird_in_Austin]

Thanks. I have to use a vertical die to land size and the best vertical is no vertical

[@PatAutrey]

Are you putting your antenna tuner in the shack or at the feed point? What would you say the minimum coax length should be to avoid unnecessary losses

[@timg5tm941]

On 80m lengths beyond 20 feet begins to leak loss

[@PatAutrey]

@@timg5tm941 thank you sir do you keep the tuner inside with you or is that outside at the antenna

[@davidryeburn6446]

On 30 m the pattern shouldn't be too bad but the impedance at the bottom of the antenna would be very high because it's just a bit short of 1/2 wave long. A higher ratio unun switched in for 30 m only might take care of that problem, David VE7EZM and AF7BZ

[@timg5tm941]

Indeed. If we say it’s around 3,000 ohm then a 4:1 might get it within the range of a decent auto tuner.

[@jeffdyer2393]

Can a ground mounted vertical like this be feed with 300 ohm twin lead? Would solve most of the lose.

[@timg5tm941]

You can try but balanced feeder will in all likelihood begin to radiate if feeding a vertical and running along the ground. This brings the potential for rf in the shack. Plus it’s anyone’s guess what impedance is then presented to a tuner if you use 300 or 450 ohm ladderline rather than 50 ohm.

[@robertbobbitt8448]

or a tuner with a built in unun

[@KD9ZHF]

Could you also do better with an autotuner at the antenna?

[@KD9ZHF]

Oh, I should have finished watching the video. You answered it in the Pros/Cons

[@timg5tm941]

You got it 👍

[@ArduinoAlan]

why does the SWR get worse on 10m with the unun?

[@timg5tm941]

Impedance lowered even further I would assume

[@n0vty873]

Use a 9:1 unun requires much less tuner and lower losses

[@timg5tm941]

Thanks For the info

[@timg5tm941]

Thanks For the info

[@brianfields4479]

Another very good informative video. I hear many op,s the air using this ant, it obviously works very well. Ants are funny beasts, my 40m quarter wave works from 40 - 10 with a tuner, no unusual, it will have losses obviously, but I can still work eu on all bands , funny eh. Does that mean with a unun it would work better ? 73 zl3xdj

[@timg5tm941]

If there’s matching going on near the feedpoint all is well. However if it works for you then fair enough 👍

[@brianfields4479]

@@timg5tm941 the highest swr using the 40m vertical without a tuner is on 30m, where it is 3 to 1, all other bands 40 - 10m is below 3 to 1, and with a mfj tuner in the shack no probs. Bands down a little just now, but 20m long path your morning to uk from zl are good. 73 zl3xdj.

[@hyperionsixzeroeight5064]

Add an automatic tuner (SGC, etc) and throw the baluns and matchers away and connect tuner output directly to insulated vertical, just like military does on ships, only waY TO GO AND GET 1:1 ON ALL BANDS.

[@timg5tm941]

Yes a definite if slightly more expensive option.

[@johnwalker5366]

Hi Tim ,love your videos , I have been using a 43ft vertical(20yr old ex army surplus ) presently on 20m at near bottom end of garden fed by ladder line with 4:1 baluns and coil/cap network as a 5/8th. in the winter its tuned for 7mhz ,(in the past its had wire quads, for 15/10m strung on it ) I Prefer to use ferritte toriods to block fields returning on the outer coax ,and balance open ladder line as with my doublet on 80m/top band . Never heard of L/C network (antenna couplers) overheating ,unlike toriods which must be a rf loss.

[@NICKGAR7]

Nice analysis Tim. As it happens, I (finally!) did some experiments on my drive (quite noisy, surrounded by buildings) with an ELEVATED 43’ vertical with a CG3000 remote tuner at feedpoint (3m AGL) AND a SINGLE random elevated radial (probably more than 60 feet). Quite impressed by performance. Main aim is for portable antenna without wanting to lay down miles of ground radials. Next step is to try 3 or 4 elevated radials and perhaps ‘tune’ them by coiling ends up to see if much difference. I set myself a task of working 2 or 3 Qs on ALL bands 160-10 with max 100W ideally SSB within 1 hour. This I did easily however I reluctantly needed to revert to FT8 mid evening as needed to keep the noise down. Proximity of antenna (back of motorhome) led to some RFI on some bands which I think I have traced to poorly shielded sound interface lead. Looking forward to getting out in ‘the field’ (1400 feet, no people around) to further test with a couple of added ELEVATED radials and do a day n night session including greyline. Of course, pushing up an 18m Spiderbeam pole needs some added tools but I believe this is a potential ‘go-to’ all bander for portable ops with decent all round performance. A good base/mast mount is of course needed. Antenna can be unguyed in calm conditions too (less faff with guys as with ground mounted radials). I also want to experiment with connecting ATU counterpoise stud the miles of barbed wire fencing up at my site. Band condx during my test (9 Oct 23) were good inc USA on 80m, deep into EU on 160 and lots of SA on 17-10m. Per your plots, the 17-10m could theoretically be bettered with the smaller ‘33’ foot vertical’. Remote tuner at base is way to go. I think elevating takes the stress out of laying radials when portable. I guess the next step (for me) could be a higher power-rated REM-ATU! Cheers for now Nick M1DDD

[@timg5tm941]

Great stuff! Those remote feedpoint tuners are a god send I agree

[@dxscotland5901]

Hi Tim I built a 43ft vertical a few years ago and had a homebrew tuner at the bottom.It was rubbish on 20m but unbelievable on 17m as I regularly worked dx! Thanks to your video I now know why it was poor as I didn’t put a 4:1 inline! 73 Gm4zji Chris

[@timg5tm941]

Ah! Likely to be the case!

[@GoonyMclinux]

I always cut mine for a 5/8 wave on 20 meter (which the 43' is pretty close to anyways) and used a simple LC network and mine was a DX hammer.

[@Ei2iP]

Tim, how about feeding the vertical with ladder line? Doable and or acceptable?

[@timg5tm941]

I think feeding an unbalanced antenna with a balanced line would see lots of common mode issues? Also, ladderline shouldn’t rest on the ground for the same reason

[@daveengstrom9250]

What if one used a 9:1 UNUN? Would that help the SWR?

[@timg5tm941]

It could do but the length and type of coax used would still change the impedance that a tuner would need to deal with and present loss before it reaches a tuner.

[@timdbl7804]

Hi Tim, thanks for the analysis. I wonder how much more rx cosmic/sky- noise is delivered by the high angle lobes on the bands above 14 MHz. I think I have also somtimes experienced cloud-noise from heavy shower-clouds, not even when it is thunderous! 😮

[@hp7093]

This is the best and only video you need on the 43 foot vertical. I know so much more than I did after watching this. Thank you

[@timg5tm941]

Thank you!

[@che59v]

Tim, please haver a look at a book called " ANOTHER LOOK AT REFLECTIONS By: M. Walter Maxwell, this book stands against most of the information your brought forward. here is an example: " The relative unimportance of low SWR when feed-line attenuation is low is demonstrated rather vividly in the following two examples of spacecraft antenna applications. First, in the TirosESSA-Itos-APT weather satellites, of which the entire multifrequency antenna-systems design was the work of the author, the dipole terminal impedance at the beacon-telemetry frequency (108 MHz in early models) was 150 - j100 ohms, for a VSWR of 4.4, reflected power 40 percent. Matching was performed at the line input, where it was fed by a 30 milliwatt telemetry transmitter. (We can't afford much power loss here!) The feedline and matching-network attenuation was 0.2 dB, and the additional loss from SWR on the feed line was 0.24 dB (5.4 percent), for a total loss of 0.44 dB (9.6 percent). On the prevalent but erroneous assumption that all reflected power (40 percent) is lost, only 18.1 milliwatts would reach the antenna, and efficiency, determined on the same erroneous basis, would be only 60 percent. But 27.1 milliwatts were measured; of the 2.9 milliwatts lost in total attenuation, only 1.6 milliwatts of it was from the 4.4:1 VSWR. So the real efficiency would have been 95.5 percent if perfectly matched at the load, but reduces to 90.4 percent by allowing the 4.4 VSWR to remain on the feed line" "

[@timg5tm941]

Thanks Joe .. noted 👍

[@nr3rful]

That antenna is my home base go to antenna. Up for over 10 years and love it

[@DAVIDGREGORYKERR]

What about replacing the 4:1 UNUN with a 9:1 UNUN or a 16:1 UNUN and seeing if the SWR goes down to 1.5:1

[@timg5tm941]

The 4:1 is used to being the wide range of swr to an impedance that is presentable to a tuner. The other ratios are too hit and Miss across all the bands

[@dougtaylor7724]

Tim, I wish you would get a Zero Five 43 foot ground plane. It actually does what everyone says their 43’s will do. And what a FT8 machine it is.

[@timg5tm941]

Interesting Doug ill check it out

[@VE9ASN]

Great video. I'm curious the SWR calculations with say, a 5 or 6 to 1 unun? 73.

[@timg5tm941]

Hmmm interesting

[@jest.s50si83]

Thanke you for every informatione by S50SI 🇸🇮

[@timg5tm941]

Thank you’

[@robertkennedy1960]

If you are worried about feeder line losses, why not use ladder-line instead of coax? A simple solution!

[@timg5tm941]

Feeding an unbalanced antenna such as this one with balanced feeder like ladder-line can be done. But watch out for rf in the shack which would accompany it in all likelihood

[@timdbl7804]

....And the ladder line would radiate..... unless using a balun at both ends

[@AliReza-zx8km]

Nice...............

[@timg5tm941]

Thanks

[@JReed305]

Just out of perverse curiosity I would have liked to have seen the pattern on 160.

[@timg5tm941]

Yes I knew someone might say that. The pattern is similar to 80m or 40m.. but the efficiency and feedline loss?? Ouch!

[@JReed305]

@@timg5tm941 Indeed no where near efficient at all.

[@johnflowers1976]

Hi Tim, I've heard of some folk using the 43ft with a 9:1. What's it like with that I wonder? 73 G0JLF

[@timg5tm941]

Hmmm I think for 60m where impedance is going to be low as it’s a 1/4 wave it might be problematic.. otherwise, I’ll need to check that one out. I suspect things should be ok, especially if the tuner is in the shack.

[@theradiorover]

A 43' radiator and a 17' counterpoise works as a "random wire" with a 9:1 connected directly to the radio (one containing a tuner). This is often used by portable and qrp ops. It can be used with an external tuner too.

[@timg5tm941]

@@theradiorover good point Fraser. Only downside i would suppose are the higher lobes above 17m.

[@theradiorover]

@@timg5tm941 yes, it's never resonant, just convenient. I only use mine on really lightweight trips. Signal reports are always a couple of S-points down.

[@COASTALWAVESWIRES]

I was about to ask the same question about using a 9:1 as well when I saw this reply. I’ve used a 9:1 with a 41 foot wire with pretty good numbers. I’m sure 43 feet makes a considerable difference. Interesting video Tim!

[@stanholmes4293]

Thanks for the video, I use a 35.5 Ft slopper. Works well into Europe mainly QRP. What moddeling software do you use? Regards

[@timg5tm941]

Thanks Stan. Glad the antenna works well. I use MMANA-gal software. 73