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DIY: 3D printed case and winder for EFHW

Hello everyone,

Used the rainy Sunday for a bit of antenna DIY activity.
Outcome is a case with included winder for an end-fed half wave for 40/20/15/10m based on the classic EFHW design using an FT 114-43 with 2 primary and 16 secondary windings.

3D printing files shared here:

In addition I added to my version a link connector (3mm plug) and tuned another ~ 7m to add the 60m band to my setup.
This gives me 60/40/20/15/10 m bands in one compact package.
The wire used is the ‘Antenna Wire - lightweight’ from the well know shop with SOTA in the company name hi
It is soldered to the enamel wire, shrinking tube added and folded back thru the arrangement of holes to build up friction.
3 holes at the winder edges allow mounting of guy ropes

Looking forward to bring it on the air.

73 Joe

20 Likes

Hi Joe, thanks for contribution. A great idea. :+1: :grinning:

73 de Geoff vk3sq

1 Like

That’s pretty cool. Do you use a counterpoise wire and if so, how is it connected?
73, Fraser

Hi Fraser,

No I use the version that connects the secondary to the coax shield. And there for use a choke before the transceiver.

But everyone is free to use the box as desired. Also a 9:1 for a random wire can be installed.

73 Joe

1 Like

Hello Fraser,

I think it is not complicated to make a hole in the box to enter a counterpoise and solder it to the ground of the BNC socket, generally a length of 10’ should be sufficient :wink:

73 Éric

1 Like

Cheers Eric.
Yes, I am aware of the way one could do that. I just wondered if it was incorporated into this design but maybe not visible in the photograph.

73, Fraser

I can include it in the design as an option.

And of course if there are ideas for improvements please let me know.

73 Joe

1 Like

And here is the new design. Thingiverse project is updated. See link at first post.

The new design has 3 extra holes for a counterpoise mount. Just a small hole needs to be drilled.
Also the holes for ropes fixtures are larger to make it easier to mount carabiners.

And 3 new lid designs are added. Of course one dedicated to SOTA hi

73 Joe

5 Likes

There is no need for a counterpoise. The coaxial shield does the job. I recomand a length of about 9m, but 2m also works well.

73 Chris

2 Likes

RG174 is ideally suited as coaxial. At a length of 9m the attenuation is max.1.5db at 30Mhz and can be neglected.
RG58 is too bulky for me and only max 0.5db better then RG174 at 30Mhz.

1 Like