HAM RADIO: Dualband Antenna, How They Work.. and other stuff

OK before I get a shed load of abuse Please note, my math is not perfect and this is only a partial explanation that will try to show the relationships between the frequencies shown, and it's not to be taken as the definitive answer. ( this is my understanding and it works for me).
The impedances top and lower readings are to demonstrate possible readings and are not necessarily a true reflection of the values you may find.
In short this video is intended to help explain how dual band antennas work.
I'm still learning and any comments to correct or confirm my belief are gratefully received.
Please subscribe and like.
Cheers
Mike - M0MSN
P.S. do not take my word for it, give it a go for yourself.

[@robmcfaddin768]

This is really good. Very clear in explaining why 2m 440m are compatible in an antenna. Please keep these videos coming.

[@UKYak]

Brilliant. That has helped me dramatically in my antenna principles education. Thank you.

[@robertmitchum2972]

Excellent video...... You explained the 3rd harmonics of a basic dipole perfectly! In fact, your explanation was so good it shed some light on simple calculations for 3/4 wave antennas on the HF bands. I’m going to get out my coil of wire and try some builds in the very near future. Next, you should explain the harmonic characteristics of a loop antenna.

[@mike-M0MSN]

Glad it was helpful!

[@DXCommanderHQ]

KZbin just recommended me this video to watch Mike.. So I did!

[@mike-M0MSN]

Why thank you. ❤️

[@sarto7bellys]

Thanks for making this vid, things have become much clearer and I've also learned how to use the bloomin' calculator !

[@mike-M0MSN]

You're very welcome!

[@4nk8r]

Great video Mike:) great info , you made it easy to see the math behind antennas

[@mike-M0MSN]

Thanks 👍

[@richardaldom741]

Mike you crack me up. Actually a very nice explanation but I do think that Callum needs to help you on your drawing skills. Enjoyed the video, looking forward to the spiral follow up as I am looking at winding an off center fed 40-6 dipole to hide in plain site from my HOA.

[@kit121]

Thanks, this is a great video and dose help me a lot for the antenna knowledge.

[@wfwtheradioguy3414]

Nice job explaining that, Mike.....that's clear as mud now. 😉 Just kidding....it made perfect sense and was a great refresher. Thanks for sharing. 😊👍

[@mike-M0MSN]

Thanks 👍

[@simonhammond5904]

When you get a fractional answer, If you press SD button on your calculator it gives your answer in decimal. No need for the ENG button unless you want your answer to a power (index)!

[@mike-M0MSN]

Hey thanks Simon.

[@RobB_VK6ES]

You can blame the education system for the abortion that is algebraic calculators that try to emulate the equation as it is written down. I am so glad that I transitioned to RPN back in the eighties. No need for brackets or equal keys and every intermediate result is displayed allowing sanity checks all through the calculation.

[@viktorkuzya5300]

Спасибо, вполне доходчиво. Очень интересный канал, смотрю сейчас по очереди видео, много полезного узнаю! 😊

[@BoB4jjjjs]

5 bananas 👍👍 simplest way I have seen of explaining it. 😎😎

[@JReed305]

Have to love the beauty of harmonic frequencies,

[@mike-M0MSN]

Couldn't agree more!

[@PatAutrey]

Field day is coming up soon and I'm concerned about operating in such close proximity to other radios I'm wondering if you have any experience with this and what can be done to protect the radio I'm using a 991A by Yaesu

[@xandear1]

Hello Mike. Your explanation was really good! You are a very funny guy. Hugs from Brazil.

[@mike-M0MSN]

Hey, thanks!

[@ohyeawhosurpoppy]

Nothing like Engineering Math to get your mind off Valentine's day and back into focus. 3/4 stick gets you more bananas 👍

[@mike-M0MSN]

So true!

[@Rubedo777]

Thank you for this explanation. 💎 💙

[@mike-M0MSN]

Glad it was helpful!

[@stoikiymuzhik_high-schoole1057]

easy to understand for someone like me having nightmares on mathematics :) -73

[@woodybollox]

Hi Mike. It wasn't the worst mate it was a great explanation. Cheers bud.👍

[@mike-M0MSN]

Thanks 👍

[@azzamdernayka2249]

Very clear, thanks. I built this 2m quarter wave exactly the same way you did with swr 1.06 using HT (5w) but when i connect my 50w rig swr reading shows 1.64 and power showing only 30w ( i am using same swr meter shown in skylab video) any possible reason?

[@mike-M0MSN]

Not sure why that would be, may be the materials used??

[@g3rcq]

Regarding the Frame Antenna - put a couple of varicap diodes in place of the variable Cap and feed the voltage along the feeder - I have one for 80 and one for 160 which also has a second frame that is also switchable from the shack to give N/S and E/W

[@timtaylor8557]

Do you know how I would go about tuning a dual band base antenna to be resonant at a higher frequency like 467? This is a tram 1480 5/8 four element. There is no tuning ring.

[@chiphungerford]

Makes Sense Mike, but where does the longer antenna benefit us? Say a full wavelength or a two wavelength antenna can we benefit from the longer antenna or is these a point where more wire does not benefit the TX / RX. Or how about an array or 3 quarter wave antennas would that provide a better TX /RX just trying to understand what makes a better antenna.

[@mike-M0MSN]

ah yes this is co-linear stuff will have to do a video on that, but quick answer if you have 2 or 3 x length it flattens the far field patten increasing gain (less power is lost to the sky)

[@Mottersmotters]

Great video Mike loved the diagrams thanks. I want to build a efhw at some point. Motters M7TRS 73

[@mike-M0MSN]

Go for it!

[@DonzLockz]

Good to know and to jump start my brain doing maths again.😆👍

[@mike-M0MSN]

😁

[@mikecampbell410]

Thanks Mike. Grate explanation !

[@mike-M0MSN]

Thanks 👍

[@sergiocavazos8963]

how did you calculated 3200 ohms at the end?

[@mike-M0MSN]

I didn't, it is a impedance figure taken from the end of a wire antenna and used to demo the relationship of the impedance you could expect to see as you move a way from the null point on a dipole antenna.

[@stewpot3971]

Thanks Mike, great explanation!

[@mike-M0MSN]

Very welcome!

[@adyg6ad73]

Great content as usual Mike. But I don’t like the effects you applied up to 0.58 at the beginning of the vid.

[@mike-M0MSN]

Noted!

[@jochenkrebs9685]

Is there any chance for the Imax2000 Projekt ? 73´s DH1KJ

[@mike-M0MSN]

Yes just waiting for the bits and bobs so there is no cost.

[@sveinfarstad3897]

Thanks Mike, i like this video.

[@mike-M0MSN]

Thanks 👍

[@johnbidgood8903]

Very clear thanks

[@mike-M0MSN]

You are welcome

[@juliem1595]

Good job thank you

[@izzetmuroz]

Good video Mike....

[@mike-M0MSN]

Thanks 👍

[@WaltKO4LFE]

K04LFE 👍 Thanks Mike! Good video...

[@mike-M0MSN]

Thanks 👍

[@mccooperman]

Thank you for explaining this Mike … answers a few questions for sure … explained really well… excellent 👍 👌

[@mike-M0MSN]

Many thanks 👍

[@pu4mksmarkussalustianosalu783]

Muito bom obrigado aí antena muito boa todas as bandas

[@ianxfs]

Thanks Mike. If only you had three hands….

[@mike-M0MSN]

humm yes

[@adelarsen9776]

Generally speaking one should know how to work out an antenna's frequency by looking at it.

[@mike-M0MSN]

Yes, Diamond 510 is a great example, :)😉👍

[@stephenwade8093]

144 to 148 in Australia

[@matknight]

Hello Mike, do you have a contact email i can send you a question?

[@mike-M0MSN]

look on QRZ