Buddipole Coil Slider

thingiverse

I really like the Buddipole (https://buddipole.com/) antenna system, and while the taps they provide are very good for solid connections, I really dislike moving them particularly when wanting to fine-tune coil settings for a given condition, particularly when you're using the dipole and want to test moving the taps on both coils. My sausage-like fingers tend to drop either the retaining ring or the hook. I created these coil "sliders" (you need to depress, then slide, otherwise you'll probably bend the contacts) to make exploring different tuning easier. I recommend using their taps once you've found the right setting. The minimal contact area between the banana plug and the coil wire is probably not the best setup for high power applications. For that reason, the sliders have a specific carve-out to allow the existing taps to stay attached.This also requires (per coil, double this if you're using the dipole version of the antenna)Springs from 2 ballpoint pens2 M3 nylong lock nuts.2 M3 screws at least 30mm long (recommended to use countersunk heads)1 2mm banana plugs (1 each male, 1 each female). I used these: https://www.amazon.com/gp/product/B07H97G7NYCyanoacrylate glue ("superglue")1 ring terminals with > 9.5mm ID ("yellow").Some wireOptional: hacksaw and/or file, and pliersAgain, double that if you're making two coil sliders.Assembly:Print the upper and lower portions of the sliders. The only part that really needs supports are the bottom long spans on the Coil Slider Upper.Press-fit the M3 nuts into their recesses. A clamp or pliers may be useful.Feed the M3 screw through the top hole of the Upper, through the hole in the lower, then through the center of the spring, and tighten into the captive nut. This doesn't need to be terribly tight, it's just serving to keep the springs captive. See photo above for layout.Optional: cut into the end of the female banana plug with a hacksaw, then file it out with a triangle or circular file; the goal here is to make a "fork" at the end of plug to increase the contact area with the coil wire.Insert the female plug into the upper slider and text fit. You may need to rotate the pin so the fork of the pin seats best. After this is done, I recommend adding some cyanoacrylate glue to the pin on the inside of the slider. Don't get any inside the pin, as you may not be able to insert the male end into the outside of the slider.Since Buddipole uses really nonstandard banana plugs (for my neck of the woods, at least); they are something like 2.5mm. Which means unless you're able to source some of those, you can't re-use the existing plugs. Fabricate a new one with a ring terminal, a length of wire, and the male end of the 2mm banana plug. Screw ring terminal only the end of the coil, and insert the 2mm male banana plug into the end of the 2mm female socket on the coil.Set up your antenna and start tuning.One option to save on some of the items is to bore out the coil banana plug, and screw in the OEM plug into that. This probably means you'll be contacting 2 adjacent coils at the same time, so take that into account while tuning.