[Yet another area of agreement, Richard]
I’ve always thought my soldering skills were pretty good having been trained by the best [professional electromechanical trainers on Marconi EEE apprenticeship course c.1969] but I stopped soldering delicate PCBs having 'lifted’ a track/trace when trying to broadband my FT857 for 60m [I had to send it off to a UK dealership who did it properly for a reasonable fee]. But yes, despite my poor near vision in recent years and need to use magnifying glasses, I still make antennas, connector cables and similar. Good to keep one’s hand in.
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I was watching Fraser’s video on making a 2M flowerpot and suddenly realised I think we are talking about a slightly different antenna, maybe the flowerpot is a TLT whereas the Thunderbolt has a larger coil and a matching stub. If anyone has a 2M Thunderbolt, can you let me know the dimensions?
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Is that the same as the slim G?
If it is, open the tube at the bottom and check the ladder line hasn’t broken at the joint and needs soldering back on.
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I don’t think that can happen as these are made commercially and not home-brewed 
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It has plastic, I am the Robert Oppenheimer of anything plastic, I can literally touch the stuff and it will shatter (I am the destroyer of plastic!)
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Agree - and performs equally as well
It appears Nigel of Hawkins Radio seems to have retired making his antennas which is a shame, the 2M 5/8 wave Thunderbolt is fairly easy to replicate as it doesn’t need a matching stub. Last year I realised my 10M Thunderbolt had gone missing, still can’t find it so I need a replacement, like I said it is the matching stub that is the problem. Nobody seems to know how to make one
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Was this research paid for by Fosters? Apes can learn between 100 and 1000 words. That at least enables them to use the internet and post questions and answers. The writing of a paperback banana Western by a group of collaborating apes seems feasible. Heck I think I’ve encountered a couple on the air.
73 and ook
Ron
VK3AFW
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Andy,
Its not guaranteed that you get quality if there is a fancy sticker on the outside. My Xiegu failed on SSB due to a poorly soldered mic wire while on a dxpedition.
73
Ron
VK3AFW
There are designs on the web for inductively stub tuned 5/8th antennas for 2m. Scale by 5.1 for 10m.
You actually have a physical example of such a design in your hands. Remove the heatshrink, measure sizes. Scale by 5.1 for 10m. Make one. Measure and trim or extend as required. Make a another production version. Apply heatshrink to both.
Consider going into business making them when you see how simple they are.
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Hah! The BBC article says only that the two researchers are based in Sydney. Can Fosters even claim to be an Australian beer any more as it looks like it’s no longer brewed in Melbourne but rather down the road from me in Manchester.
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I think you missed the part where I said the 2M version doesn’t need a matching stub, so it’s probably easy enough to make; however, if you haven’t had a close look at one of these Hawkins Radio antennas and I’m talking about the 5/8 wave versions for 4,6 and 10 Meters then you won’t know that the quality is exception and not something that will fall apart in 18 months!
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In the video you posted of a 5/8 Thunderbolt,at 1:13 James talks about the matching stub whilst showing it to the camera.
One of you is (to put it politely) is mistaken.
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The 7/8th wave version doesn’t have one, but you are correct; the 5/8th wave does have one. Actually, the 7/8th wave is a Viper, not a Thunderbolt so that’s the difference. Thunderbolts have a matching stub, and Vipers do not.
The amazing thing is that every time I ask *Does anybody have any information about the matching stub?" I just get people posting about the T2LT or similar-looking antennas, which do not have the matching stub
Basic antenna theory. A 5/8th has plenty of capacitive reactance and often they look like
80 - 500j Ohms. So you add some inductance to mix, oh at a guess +500j Ohms! Then you have a nominally 80Ohm resistive antenna which will have an SWR of around 1.5:1 in a 50Ohm system.
Theory is one thing; no one has any plans on how to make one. This has been admitted in several places on the interweb, it is deemed a ‘tricky exercise’, what capacitor do you use?
By measuring what you have and applying the stuff in the theory. That’s not even rocket science. Someone has done the rocket science and written it up in all the books / articles you can get for free. There’s never been so much free information available.
Here’s the forward to Antenna Impedance Matching published by the ARRL.
Note the words: “Complex matching networks can be developed by using the Smith Chart. No special expertise is needed.”
No special expertise is needed, applies to lots and lots of hams who do not have a technical / electronics background. It gives loads and loads of examples on how you actually match the antenna from the measurements taken.
Make antenna, measure antenna, follow examples in book, make matching components (tells you how), add components to antenna, measure. Amaze yourself you’re now as clever as the Hawkins guy.
You don’t even need to buy a copy as you can download it for free.
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I always assumed the Hawkins antennas were rescaled copies of the Gainmaster design from CB, which is fairly well-documented although you would have to rescale it for the frequency of interest yourself.
The Thunderbolts (5/8) are indeed copies of the Gainmaster design, although a little refined and of better quality. He also made the Vipers, which were basically T2LT. All I need is the dimensions for each of the required bands, 10/4/2, also the Hawkins Thunderbolts that I have had all have SO239 connectors where the matching stub is, which makes the 10 and 6 metres easy to pack away. Putting a connector immediately on a stub looks very awkward.
Regarding the stub, I was told they were made out of Westflex 103, while the rest is RG58. Westflex 103 isn’t as easy to get hold of, I certainly don’t want a big drum of the stuff! So I am wondering if Ultraflex 10 would make a good replacement?
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