Using a 3D printer to make a loading coil for HF portable or static mobile operation.
On Thingiverse I found some files to download and make a loading coil, by VA3TNE, here
https://www.thingiverse.com/thing:2352109
It is designed to work with a folding 'tank whip' or 'Manpack antenna' or AT-271 folding antenna - Google will bring up some useful links.
I printed both the long and short coil versions and found the short coil best suited my needs as it loads the 'tank whip' anywhere between 40 to 10 metres, which is all I need, although the long coil will tune to 80 metres, but it is very twitchy down there.
The coil wire is 1.6mm stainless wire and the end fixings are 3/8in UNF stainless bolts and stainless half nuts and a brass nut - the long brass nut is for old car exhaust manifods and everything can be found on eBay UK and other UK internet sites.
Tuning adjustment is achieved by a sliding 'short' with fly-lead - I used a Stainless 'Jubilee' clip as opposed to the original idea of a 'crocodile' clip, which is why the coil form has 5 vertical cutouts to facilitate the use of a crocodile clip.
The Jubilee clip is tightened enough to just allow it to slide up or down, but not so tight as to clamp it.
I had a broken camera tripod, so dismantled the broken head and 3D printed a bracket to mount the coil and some radials/counterpoise. There are 3 short fly wires on the tripod mount and have gold plated 2mm 'bullet' connections for each of the radials, so they easily pull out if someone steps/trips on a radial and easy to disconnect and coil up for transportation.
How it looks on the tripod for portable work (click the images to supersize)
The Slidewinder DX Coil Is not this thingiverse design at all. It is our own design nothing to do with this thingiverse stl file. We have nothing against you making your own coil but please Don't the link this blog page to our website. Because what you have made isn't anything to do with what we are marketing As Slidewinder DX.
ReplyDeleteSlidewinder DX Is a brand name of M1ECC Antennas.
Slidewinder DX Design is the intellectual property of M1ECC Antennas.
Remove our website link from your blog asap.
As its miss leading information.
Hello M1ECC, I have removed the link to your website as requested. I didn't realise that you had made your own, completely independant design of the very similar original design by VA3TNE. At least I am not guilty of plagiarism as I have linked and given credit to VA3TNE's original work, even though I had to modify the end caps to suit the hexagon A.F. size of the 3/8" UNF nuts. If anyone would like the modified end cap stl files I created, please contact me and I would be happy to share them.
DeleteThank you G4ZAL For removing the link to our website, As it was very miss leading information, We wish you luck with your endeavours using the Thingiverse VA3TNE design.
Delete