This fried the final in my radio! Not to say your transformer in itself did it directly. But my cspacitor came loose and broke connection, therefore the ground and center became a direct short! So, people, make sure you soldier the cap well, or have some kind of SWR meter slways on with this trick.
Nice radio. The vswr should be 1.2:1 OR LOWER at the chosen frequency. I have made several and I use the FT240-43 x 2 stacked as I use 400 watts as an amateur. I also use a single FT240-43 as a coaxial current choke betwen the coax from the radio and the bnc connection you use. This improves the antenna system by giving the efhw something to drive against in the absence of a ground and gives a more accurate vswr scan as any standing waves on the feed line have been significantly reduced. Cheers VK5LB.
Your videos might be long, but don't worry you explain everything so well, me with limited knowledge of this subject, is learning so much from you. Thanks. What wire is best for the antenna, or can I use any wire.
I find that fine grit sandpaper or an emory board removes the insulating varnish from wire quite nicely without risk of damaging or breaking the wire. I have also heard that you can heat the portion you want removed with a lighter for a minute or 2 helps soften the varnish and makes it easier for the sandpaper to abrade the varnish off And you can always check your work with an ohm meter..
Hello from Mexico, I am pretty interested on building this antenna for an old Cobra 148 GTL, this antenna seems to work for 10 and 11 meter according to your antenna analyzer which is awesome, I would like to know what type of cable you can use for the antenna. Also at the end of the video you mentioned that you need to trim the antenna (wire) to a certain meters (using a calculator the wire the recommendation is 5.22 m for 27 MHz) at the end which was your measure and also at the end of the tip how do you end? do you use a cover, I saw the other video were you made this same one but the SWR was above 2.0 an this one is between 1.5 and 2 which to me looks great. I am pretty new with no experience at all, so any help is very welcome! Will be nice to know more about HOA antennas because I see they work well for all bands, but is you know a way to build one specific for 11 meters will be nice to know. THANKS!!
Lubec is not far from me. I am down the coast a bit from there. Were you ssb on CB frequency when you made that contact? I have never heard a meaningful contact on CB, usually only 10k watt stations skipping in with rubbish.
@@RadioPrepper Ok, thanks. I thought it sounded to civilized for 11 meters. Thank you for the continued videos of making baluns. I will some day get the nerve to try one.
How does this compare to a half wave over a quarter wave Jpole? Aside from the Jpole being longer?? This is my current setup wire base antenna and it does great. Just wondering how much better this would be...
Why do you always only use end-fed antennas? Are dipoles not more effective? :) Again, t2lt is better for CB. Easy to manufacture and no need to solder anything at all. Well, except for the connector. :) And why do you always use round ferrites? Direct ferrite will be even more compact. Sorry for the stupidity, just curiosity.
There are no stupid questions. End-feds are just easier to use, faster to deploy, and when vertical have a low angle of radiation. Round toroids are just easier to work with as well. Performance is not everything, sometimes ease of use is more important..
Good stuff. End fed half wave antennas are good for multi band use, such as 20 and 40 meter or 10 and 20 meters, but in theory, the lowest angle of radiation from an end fed antenna should be about 0.65 wave lengths long. Any length of wire can be matched to the transmission line, but longer than about 0.65 wave lengths, the angle of radiation begins to increase and that is not desirable. A 0.25 wave ground plane needs to be at least 0.25 wave lengths above the ground to reduce ground loss. From this it was thought that end fed antenna should be at length one antenna length above the ground. Accept a funny thing happens with an end fed half wave antenna. The ground loss is greater and to reduce the ground loss to that of the 0.25 wave antenna, a half wave need to be a full wave length above the ground. The end fed half wave can suffer greater ground loss, even though it might have greater gain. That brings us back to the 0.65 wave end fed wire antenna. The gain is greater (low radiation angle) and it only needs to be a half wave length above the ground to reduce ground loss. Anywhere between a half wave and 0.65 wave length, should increase gain and reduce some significant ground loss if the bottom of the antenna can't be a full wave length above the ground.I would try matching an end fed 0.65 wire antenna and getting the bottom at least a half wave above the ground.
Preppers, do yourselves a favor if the time comes where you need to survive. Don't use CB. Short burst of traffic not long enough to be Fox hunted. CB I guess if you have an established network, certainly not in a single person survival situation. Hey that's my take on things.
Positive name recognition takes one second. Negative recognition is forever...Three interruptions, so far...advertisements louder than video... I will not support any advertiser whose ads do not have an option to 'opt out' immediately. I encourage all other readers to re-post this statement to start pushing back these interruptions...
Thanks to your videos EFHW is my favorite antenna and my first homebuild project, tested last summer on CB 11m, with it I did my first DXs with 5w only 😀. Now I upgraded it for ham bands! What is still not clear to me is if some improvements are expected with a counterpoise wire, I use it without “grounding” and I have no issues and no RF backflow...
Merci Gil pour cette video tres instructive. Il faut preferer surdimentionner les transfos pour eviter tout signe d'echauffement : echauffement = perte d'energie, tout ca c'est du rayonnement qui n'est pas fait. Donc ne pas lesiner sur le nombre de ferrites. 2 grandes pour 500W, 2 moyennes (1 pouce de diametre) mininum pour 100W parlant de SSB. Et bravo pour le QSO avec le Maine !
Build a 11 meter j pole out of aluminum tubing I made one out of copper pipe I pipe a 102 cb car will antenna on the top of j pole it was 27 long short side 9 foot long
Nice work. We still have 27mhz CB in Australia, (US 40ch 5w AM 12w SSB) but we also have a UHF CB band, either 40ch FM @5w or 80ch Narrowband FM @5w (the extra 40ch go in the gap between the wideband channels when you reduce to 2.5khz bandwidth). We are also allowed to use repeaters, which must be public access and have backup power (most are solar with battery backup or mains with solar/battery backup) for emergency 'power out' operation. It's a class license which means as long as you use type approved equipment you don't need an individual license. Repeaters do require an individual license as they are perused for coverage/interference issues with other repeaters etc. We've got all three, some really old 27mhz stuff (from the 70s) and some modern UHF stuff, mix of 40ch and 80ch. You can work between the 40ch and 80ch radios, but the NB radios sound a bit quiet (effectively underdeviating) on a 40ch receiver and the 40ch rigs sound like they are overdeviating on a NB radio of course. There was a plan to ban the 40ch radios after a few years but it was quietly dropped when people objected. So it will probably be a while before all the old 40ch radios (you can't buy new ones anymore) all die, as there are some of the very first UHF CBs, the Phillips FM320 from 1977 still working, particularly on farms and in trucks here and there. You can use high gain antennas such as beams etc of course. My favourite 'improvised and simple' antenna for 27mhz is the inverted V which you just need a length of 50 ohm coax to make. Strip the insulation from a 1/4 wavelength, separate the inner and the outer into two separate strands. Suspend at the point where you separated them and taper the ends down at a 45 degree angle. Run the remaining coax to the rig and fit the appropriate connect (PL259 usually) and adjust for best SWR by trimming the ends of the inner and shield. Directional, at right angles to the wire. A length of fishing line tossed over a high branch works well for a suspension point in the field. Works best about a half wavelength off the ground but still works pretty well only a few feet above it.
Hi Gil, I have 2 PRC 320's, one a Yugoslavian LSB model. I will give this a try as 10m and 11m have had some good openings lately with 10m contacts on 5w across Europe. As an Idea a guide to what the band selector actually tunes to might be a good idea as I have had to learn using a frequency counter and a dummy load. I have found very little tuition on You Tube. Thanks for posting as I have no idea how to make a video! 73's M0KIA
You don't need the cap across the input, only needed for random long wire to tune out reactance, but it would be better if it were a variable cap for this purpose !
Love your video, exactly what I was looking for, I will get the materials and build one. What's your or anyone's opinion as to have this antenna as a permanent base antenna?
I watch your a older video about HF antenna 49:1 couple months ago I end up making one with 134 wire it works very well the SWR was excellent and last week I end up making one for CB just to see what it like and using 4.5 wire on 12 watts ssb on 27.405 works extremely well thanks for showing Great video.
I like your radio, too. This Manpack PRC-320, how many bands does it cover? And what kind of protections does it have as far as being able to withstand a broad-spectrum, electromagnetic "event" so to speak? Also, what modulation types does it support? Thanks. I look forward to getting more into antenna design as soon as possible, and that HWEF looks like a fun place to start. Zach, N2JZS
Very nice project. 7351. During 2 years I've made some experiences with old toroid of an old Tv, so the measures are 4,40 meters of wire to an HMA End Feed JS20 Portable/Fixed with very good results. The antenna work's very well from 20 meters to 10 meters, and also in 11 meters. The SWR is 1,4 in 20 meters and the others 1:0. Compared to other antennas is less noisy, and the RX signals up in 2 ou 3, and the TX signals up in 2 or 3 also. Now in my QTH, I'm using these new antenna with very good results, compared to an A99. Tks fer sharing and good projects. If you want any other information about these new antenna leave a reply. 7351.
@@RadioPrepper Yes, now I made four antennas. I guess I have conditions to make once a week, during a year. I´m study to make another for 2 meters and 70 cms.
There used to be a great electronics store....located south of the North train station in Paris. I loved that place. When stationed in Frankfurt, i went to Conrad’s quite often. They had most anything I would ever need. I really miss the years I lived both in France and Germany! Yes, I still have a large roll of “1mm copper wire! 😉
@@RadioPrepper unfortunately I do not remember the name. I am thinking by now it probably does not exist. So many stores like that have closed in recent years! The last time I was there was in 1995.
Bravo. Did your friend wind the cable through the ferrite core in the same direction or 5he opposite direction as your construction? Does the direction of winding make a difference?
Hi I live in Australia and the ferrite ft140-43 on Ebay are like $50 delivered , There is a local electronics store that sells Ferrites & pre wound chokes , what size Uh am I looking for in a ferrite , thanks Larry
Another great video, Gil. Built my 49:1 AT to your design 2 years ago, and it's fabulous with my pruned wires. (To date I've been switching between my 20 and 40 metre radiators. Will soon add a 30.) Everybody should have one of these things. They weigh nothing, take up no space, and get you on the air fast.
Hi gil watching your vid from reunion island French territory in the Indian Ocean I just purchased a president Lincoln II+ and no antenna yet I would like to make one like this antenna for all the band and mode on this radio and ssb also can you help please
Radio Prepper but the shield works as counterpoise and its length and position affects the final impedance and resonant frequency of the antenna. With line choke at fixed position on the coax we could get more predictable results.
A little, but not a lot with a half-wave, which is a full size antenna just like a dipole. It is just fed at the end. What you describe is for a random wire with a 9:1 UNUN, not a half-wave wire with a 49:1 or 64:1. I've had a lot of common mode current troubles with random wires, very few with half-waves.
@@RadioPrepper how about T2LT antenna in this regard by your opinion? It is also 1/2wave (dipole) but definitely required a choke at the end of feed line...
Yes but the coax shield is pretty different than the center conductor, even if they are both quarter waves. The current is not as well distributed as a single consistent conductor. I have been using these HWEF antennas for years without a choke. They don't need one at low to medium power. Random wires do.
Glad to see you back! To me, 4,5 meter sounds pretty short for a half wave. Why is it so? I was expecting something like 300 / 27 * 0,95 / 2 = 5,28 meter (insulated wire)
@@RadioPrepper if it works that's all that really matters :) I already thought using my 49:1 transformers for CB. Just change the wire, hang it and tune as required? That's convenient indeed.
Hello DK5ONV, Did you ever make the 5/8, or 7/8 wave antenna? If so what was the wire lengths for both? I live in an HOA and would like to get the best performance on my antenna. 73's and thank you
@@5940-c7w Yes I did. But not a wire Antenna. 5/8 and 7/8 was a Groundplane Vertical made of Aluminum Segments. one had the Full Lenght and the other One was shortened with a n extension Coil. I don't know about the Area where live...how much space capacitiy the Property has but a 66ft. EFHW for 80-10m could find room there to work as it should in its basics
Not exactly a dipole, though it uses a half-wave wire, fed at the end instead of the middle. If horizontal, better use a dipole. If vertical, use the EFHW. See my other videos on the antenna..
Hello !! Greetings from Andorra. I'm trying to put an antenna CB with a magnetic base on a small stand of my roof next to my window, but .. there's no way to get ground plane .... inside the house a short distance from the window I have radiators and everything Type of things where the magnetic base is hooked and I'm sure I would have a good Ground Plane .. So my idea is ... Two magnetic bases could be connected? One on the roof near the window with the antenna, the cable of that base would be the entrance to the other base .. The one that would be put at some good place .. and of the latter to the radio station .. I could work?
hello there, I can't buy an antenna at the moment for my car CB radio 4-5 watts. can you please somehow help me DIY an antenna to use till I get a real one? I am an electronic engineer but i have no information about antennas and I feel so bad about that.. I feel my self like a neanderthal human when I see people building DIY antennas. I have all the tools needed just please explain how to build one for the car or for my balcony.. whatever is more easy for you to explain
@@RadioPrepper its not a problem for the car or the home. I just want to build one to use my cb radio. Witch one is easier to build? I ordered one in AliExpress but it will take 40 days to come.
