Efficient Antennas for New Licensees

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Many new licensees become frustrated due to poor performing antennas, despite these antennas being sold as multi-band miracle solutions. Here, I cover the basics that I wish I'd understood myself when firstly licensed.
Many years ago, the miracle-antenna was the G5RV. Now this has fallen out of favour and end-fed-wires and off-center-fed-dipoles have mostly replaced it. All of the above are compromise antennas that bring their own potential issues and inefficiencies, resulting in poor performance, RFI issues and ultimately much frustration for the operator.
Here I cover the two basic, resonant, efficient and cost effective antennas that everyone should start with. They're also the two antennas that all other antennas should be judged against.
As I say in the video:-
The simplest antennas are usually the most efficient; with compromise comes inefficiency.

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Опубликовано:

14 янв 2021

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Комментарии : 8

@tantrispicks2440 2 года назад

Great presentation. It sounds just like a TED talk but without all the pretentious stage-strutting self-aggrandizement. 73, AJ6RE

@jfangio9260 3 года назад

I’m a new ham and was doing research for my first HF radio and antenna. The antenna subject is a quagmire and your advice for a beginner is really logical and makes the most sense.

@stevemcnaughton-kb3jc96 3 года назад

Nice video, my basic advice for new hams is put up a dipole if you have the room. If they don't I would go with an end fed half wave, they might need a tuner however. In my yard for example I don't have room for a dipole, so I'm using an EFHW with a tuner. It's not the best antenna for my area by any means. I like to operate portable when I can, where I have room to put up a dipole (I use a 20-30-40 linked dipole). I've tried things like magnetic loops, and small vertical systems like the Super Antenna also. But I always go back to the dipole when I can. Remember that if someone doesn't have a balun available, they can always make an RF choke with some turns of the coax near the antenna. 73 de KB3JC

@ERICtheLATE 3 года назад

That is a cool feature of the new 100w max tuners with the sweet vape mod box screens-it will click through inductor and capacitor series or parallel combinations for signal and ground side, to the lowest swr possible, but when you hook up an awful antenna to it, you will know, when it displays power from transmitter, swr, and power leaving the tuner. The difference will be turned into infra-red!!!

@alexalonso2093 3 года назад

Yes very useful.and cost savings , simplicity ,enjoyed your explanations 7 3

@alexdokic5567 3 года назад

Hi, an interesting presentation, I wondered if you have any comments on end fed half wave antennas? 73

@skeets6060 3 года назад

What the hell is a balun?

@ERICtheLATE 3 года назад

It uses tranformer theory to inductively couple two things, that need isolation, yet need to pass current through. The coax side is happy, cuz it sees a 50 ohm load, yet is really shorted to keep it's misbalance nulled, then a the other winding is coupled, yet only by inductance, to the coax side of winding, and radiating the signal. That is how it keeps the coax shield from radiating. If swr is super high, like +3:1, it can radiate back, but there is so much current in the balun, it is hard to flow against that, back into the coax, it will make the ferrite the coils are wound against warm from the rubbing electrons, as infra-red. It can be done by winding coax in 9-12 turns, in a 4" coil, over pvc, for coax/dipole decoupling, but might not work as well on all bands, because it is just a series coil and can resonate, inductively or capacitively, and you will have to trim the antenna to compensate for that, when a real tranformer 1:1 balun is very wideband, and inductively coupled, and the signal just gets absorbed by a resonant antenna. 4:1 and ununs are similar, but have a ratio of windings, to make 50 ohm coax couple to 450ohm ladder line. Or unun will just take a 200 ohm longwire, then the winding get like 3phase motors to keep it unbalanced, yet isolated, yet have ground after unun. They are good things to buy.