How to construct an aerial tuning unit for use with end fed aerials, including inverted L antennas. A simple L-match ATU for the short wave amateur ham bands which is inexpensive and easy to build. Also covers shortwave broadcast bands.
This is by far one of the best videos I have seen. I love the down to earth way you explain things. It was very educational and I look forward to building an ATU. You are right, that is what amateur radio is all about.
A nice basic video on simple antenna coupling! I wish there were more like this out there. I've been building and using similar tuners for years with good results. There are several ways to tap and/or ground the coil and to connect the capacitor, and it is fun to experiment. L-C circuits do indeed tune long end-fed antennas, and they will usually outperform mobile antennas. There are a couple of things to watch out for with end-fed wires: When transmitting, don't touch an open tuner like this (or the un-insulated antenna itself) except using an insulated knob. One (or one's shack visitor) can get a nasty RF shock. The second is that end-fed wire antennas sometimes put 'RF in the shack'. That can inflict very minor shocks when touching things like the radio cabinet, the SWR meter or the microphone. It can also distort the audio when operating voice and likely when operating digital modes as well. A good test for RF in the shack is to touch the transmitter cabinet or some other grounded equipment and see if the SWR changes when sending out a carrier. A good ground helps stop that, as well as letting the antenna work better. A simple solution to RF coming back off the antenna and getting into the equipment is to simply change the length of the end-fed wire. -- John N0BUP
Absolutely brilliant. Very well explained . Like you say people are starting from the beginning. For some one taking interest and for a Newby it is wonderful to understand components and where they need to go.
"Just like that" - I did it, with the hands, a split second before you did. I darn near fell over laughing. Tommy Cooper ,an excellent comedian, a very special man. I'm an ex-pat, living in the 'States now for the past 36 years. Thanks for bringing back a piece of the old country, Ray! 73, OM. Julian, N4JO.
I love your style... toss out the clever stuff and math... this is the down to earth basics - and then it makes great sense ;-) My type of teacher.... ;-)
Don't be too hard on mathematics, it's beautiful, even to me, who struggled with it. The struggle was worth it, especially when I finally realised that the struggle was a story I was telling myself and that I could do it.
Hi Ray, Thank you for you video. I have learnt a lot from your piece of home made ATU's. As someone returning to radio after a long break its guys like you rather than sharp suited sales reps that remind me of what proper Amateur radio is about; not money but thinking about problems and solving them. Thanks Paul M6MIY
Super video. I've been licensed for fifty years plus, but never been very active. Now I'm retired, I have not only the time, but also the space. I have various bits of kit, but I'm going back to what I loved first, namely homebrew. So far I have the PSU built, an L-match, the wire for the antenna, a half built transceiver for 80, and currently making test gear starting with a QRP power meter. Waiting for some bits for an swr bridge.
What a Wonderful Informative vidclip .... Thanks you so much .... Just giving the Very Important Basics with a good bit of banter .... :-) :-) :-) .... Keep well, Cheers from New Zealand ...
Those "Patch Leads" are called that because they're used on communications patch panels to "Patch-Off" a failing teletype, audio, RF or Fiber circuit from a bad channel to a spare good channel. I learned that working as a USAF Communications Tech at RAF Croughton, Northants in the UK during the 1960's. Love your videos. Ed/California.
Hi Ray. Just came across your videos. Absolutely brilliant may i say. No going off on a tangent, just simple how it is and how it works. I am working my way through the rest of your videos. Cheers and 73's
Hello,love the channel 👍. You should make some how to videos. You can teach people how to make there own ATU, transmitter, Meyers and that type of stuff. That would be awesome,I would watch. You tell such great stories,so thought you could teach. Just think about it,or put a video out asking people what they think about it? I think it would be great,there's a lot of people out there that would love to have you teach them about mw and shortwave transmitters and thing like that. Think about it,if you would? Love the channel,and would love to see more videos from you in the future.
These are all great videos - I'm a noise musician, interested in developing instruments that use radio signals to generate harsh sounds, and your videos are definitely inspiring!
Many thanks Ray, you have answered a question I asked earlier when you did the piece on doublets.....I love the ATU you built and find your videos/explainations so easy to watch and learn from....You remind me of an old maths tutor I had back in the 70's, I hated math but he made every lesson so interesting and funny with his laid back ways that I ended up with a O level in a subject I really hated and gave up on till he taught me.....Cheers...
I wish I studied this when I left school and had you as a teacher. Mind you I think I've learnt more on RU-vid then I had ever at school. Ps I'm a big long wire fan, planning on putting a new one up this weekend, 40m long with a small fishing weight on it with a grapple, attached to my drone and flowen across to another apartment roof, I have more fun with antennas than the actual radio 😂😂
my end fed went up 10 ft more before I could get heard by anybody, I tried all day field day didn't make one contact, once I went up 10 more ft made all the difference in the world merci beacucoupe for sharing 73 OM de n8zu somewhere in 8 land
Hello Ray, you're a breath of fresh air ! I've just got back into Radio, after a long absence, going to re-register for my licence and call signs, so your ATU video is a great reminder of all the stuff I thought I'd forgotten. I've still got the bits from an ATU I made years ago, so here goes. best wishes, Dave G0SKK( not legal yet)subscribed also
+David Chadwick Hi Dave, nice to hear from you. Thanks for your nice comments and good luck with the hobby. Keep in touch and let me know how you get on. Cheers, Ray.
Ray,I really enjoy these videos thanks .Loved the ghost story especially so if you have any more it would be great to hear them .I no longer transmit but am fully licensed and still enjoy listening and pottering around making things with Arduino now.
Hi Ray. Wow that was really interesting. Maybe what was so nice is just that I am from Irish decent and hearing you telling your story just makes me long to go visit up there. Thanks again. ZS6BVB Peter
Thanks Ray! Really good info here on ATUs. Thanks! I agree with you, Building is half the fun, or more. That is why I will always stick with my TS-830s hybrid. I can actually work on the thing myself! 73s and Cheers my friend, Tom
Fantastic informative video ray cheers . Love hearing about old radio practices, have you considered a video about simple crystal radios , building them ect
i loveed this one i have never built a darn thing in 38 yrs of bi=eing an amatuer this one i completely understood and can and will build just for fun for a tuer in the field on my LNRDD-5 i just ordered i am a decent cw op at about 18 to 22 wpm
Thank's for that lesson Ray, just what I needed as I am just starting SWL. The grey matter is a bit slow at 75 but I will stick with it as it is really interesting. Just getting my head around learning circuit diagrams and symbols at the moment. Thank's again.
I was commenting about a resonant aerial. Yes I have heard people who say that putting a matcher between the rig and coax and getting a one to one think they have resonance. and putting a 9 to 1 balun which is about 500 ohm impedance onto a long wire of 1000 ohms. ps a delta loop is about 100 ohms fed at the apex. I use a half wave open wire line which is 100 ohms impedance in to my shack and has been pruned for zero reactance I have built a home brew link coupled matcher .
Nice explanation Ray, I wouldn't rely too heavily on using cable ties as insulators though as they degrade badly in the weather (well they do here), some cheap PVC pipe cut and cross drilled will last for years and years. Cheers :)
Loving your videos Ray having just got into the hobby, you have a great style, and dont apologise for anything, love the stories and the knowledge...you briefly touched on RF earth, I was wondering if you had thoughts on how best to get a good RF earth in an upstairs flat that has the neighbours path between my door and my garden :/ It's an awkward one but I do have a convoluted path a cable could take to ground outside but it would be quite long, thanks to the silly layout of these homes. Any advice appreciated. 73 de mw7gib
Hi, the earth cable needs to be short really but you'll have to go with what you've got. Install the cable and see how it works. It's always best to try and see. Cheers, Ray.
Good video-- basic information. I like it! I use a 127 ft end fed antenna along with my Mosley 33 beam. It gives me the "odd" frequency bands that the beam will not work on. 73 - W1XWX :)
You forgot to mention that if the antenna is short for the frequency shorter then a quarter wave lengte you can switch places the coil and the capacitor to tune antenna correctly. Antenna to short =use coil Antenna to long =use capacitor
Hi Ray Have you ever spoke to a my late father on ham radio in the late 60's through the mid 70's ? His callsign was: GW8 CGH & his name was Donald ?? Happy New Year 😀
Hi ray i Keep coming back to this video , Its the best in my opinion on RU-vid,, And now ive got the bits to make my own , if possible could you advise which capacitor i should use , I have 2 of them, Both quite large , number 1 is a 500pf single stator/rotor rated at 2500v. Number 2 is a 1000pf single stator/rotor rated at 1500v . Would one work better than the other, ( cover more bands using the same length of wire ) Power handling isn't really a issue as im a foundation licence so it wil be 10 watts max for now . Managed to pick up a roller inductor from a ham fest so hopefully wont need to make a coil . Any advice/ pointers would be most appreciated cheers
I reckon that the 500pF one will be find. I think 1000pF is rather high. The thing to do is build the ATU and see how well it works. You can always swap things around if it won't mach the antenna properly.
Maybe a dumb question from someone who was a novice back in 1969 at 14 years old, but lacking a good antenna on just my old Drake 2-c receiver, would an antenna tuner help me get better reception? Or is it only suitable for transmitters and transceivers? I'll admit that I've forgotten much of the theory, but the bug has never really left. Recently retired I'm testing the water's so to speak, pulled out the old gear but expected to hear much more on 80 and 40 meters. Before I put money into this I wondered if the antenna tuner or balun would help. Any ideas?
Ray here is a daft question, maybe I am getting a blind spot. I have my receiver, and I have all the stuff for the ATU. I have made an inductor coil and have a 1 pole 12 way switch. I would like to know where the single pole in the middle of the switch back connects to. Forgive my ignorance but does it go to earth (ground) or am I reading the diagram wrong. Also I have 2 variable capacitors each about 0-500pf. As you said I will be connecting each one in parallel. Would having 2 Variable capacitors be to my advantage for my receiver. Hope you can help with this. I have a random wire aerial in the garden about 70' long about 25' in the air.
Hi Mike, the the middle connection goes to the transmitter end of the coil. The coil is then progressively shorted by the other switch contacts as you go through the positions. You'll have to try the two caps to find out whether it's an advantage. Cheers, Ray.
Ray Heffer Nice series of videos, thanks for making them Ray. I have a big horizontal quad loop, and would like to build a proper balanced ATU for it, so another one here interested in such a video. All the best and thanks again. Chris Wilson 2E0ILY
At the community radio station that I manage, the linear has a built in power meter. When I'm pushing 200 watts at the aerial the reflected power scale shows nearly 10 watts, which seems to be the suggested limit that the designer of this linear had in mind. Yet, I feel that's a little on the high side. It varies with the weather and atmospheric conditions though. Sometimes it's down to 5 watts. My question is, would an ATU help with this, as there is not one already installed? And, would the design have to be different to cope with the higher frequencies of the 3 meter band? .
Yeah, that's what I figured. It would have to be designed for that band. I would assume smaller value tuning cap & coil, or would it have to be a different circuit altogether? And I suppose, more disciplined RF circuit construction technique at those frequencies? I have a feeling that the aerial wasn't quite set up properly in the beginning by my predecessor (sadly now passed away). The problem is that it's on a pole high up on a large building so is basically inaccessible. So any solution I attempt has to be from the feed end. Maybe I should get hold of a decent SWR meter designed for that band and initially check to see what the ratio is?
im using a ez endfed wire at 32m length having issues with swr if i add a hanging counterpoise will it help reduce the swr .... i feel a project atu coming on shortly
I have an 88 ft wire going into a 9:1 unun then into a matcher and then my yaesu ft840. It covers the majority of the bands with decent results. Even tunes to 11m for some qrp local Contacts 😉
COULD YOU COMMENT ABOUT THE GROUND CONNECTION IF YOU LIVE IN A FLAT ON A SECOND FLOOR OR HIGHER LEVEL, IT'S ABOUT THE GROUND WIRE RADIATING AND WAVELENGTHS TO THE GROUND CONNECTION.
Yes, it is a problem if you live in a flat far above ground level. One option is to use an artificial ground. This video is pretty good... ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-__odbyw0o7k.html
if long wire (plastic wrapped) is going thru trees and is supported by "cruck" in trees do i need to insulate wrapped wire from from tree contact ? cheers 73
I didn't think about what I was saying...I should have known that...I did a similar setup and on receive only the reception goes up and down while turning the capacitor..but does not increase the signal.
@@g4nsj SO I pulled the trigger on the coil, got a 495 pf variable capacitor to make the ATU for medium wave...want to make a "End Fed Antenna" .....does this need some type of Balun?....or ...straight into the ATU it goes?....... also, if I decide to make something like a 9 ft vertical...can I use this ATU on that?...Thanks for the help!
Radio Workshop many thanks for the reply ,, I have watched many of your videos and one day in the near future may go for the m6 licence,,have been on the cb before and since it became legal ,,,I own a widebanded ts570d had a few hf sets over the last 30 yrs my first was a 101zd. With fm board fitted Ts 850 etc anyhow thanks for your time and effort that goes into your videos ,,,look around a lot of channels with info regarding building antennas and the like thanks Shane warks Ct1017
