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Linked HF antenna

Order and received the HF linked dipole kit and 100m of wire from SOTA Beams.
Any tips on building the antenna? Planning building for 20m and 40m to start me off.

Cheers
John

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Hi John, I’m sure you’ll get along fine. A couple of tips from my experience.

Sotabeams yellow antenna wire can be knotted easily.
The dipole calculator on sotamaps.org (extras) works well and is accurate.
I used epoxy to waterproof the entire feed point area, however I don’t use a balun. It means my 10m of rg-174 is fixed to the antenna permanently. I sometimes wish I fitted a BNC instead, which would allow me to use the RG-174 on other antennas.

Have fun experimenting and I look forward to our first S2S!

Cheers, Fraser

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If you don’t have one a NanoVNA is a useful bit of kit to get the wire lengths spot on. It is easiest used with a laptop but a PC will work if you can erect the antenna in the clear and get the feed line to reach the PC. On cost grounds it doesn’t make sense for one antenna but it will be useful on the future.

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Cheers Fraser.
I was going to use RG58 as I have a reel of it. Also look forward to a s2s or another contact!
M0WIV - I do have a NanoVNA (need to learn how it use it) and also have an MFJ antenna analyser
Cheers
john

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RG 58 is a heavier carry, but I wouldn’t worry about that. However it will put a bit more weight on the top of your fishing pole or what ever you’re using as well as the dipole centre. Just something to bear in mind. Better to cut it a few metres longer than the drop to allow you to get behind a cairn etc when operating.

There’s a program called VNASaver which runs on a PC and makes it easier to use - but you need to watch a YouTube video or two first. The calibration part is important.

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Make it so you can detach each leg of the dipole from the centre.
Likewise make so you can detach the coax from the centre.
You will need to support the weight of the coax when hanging down so that you don’t stress the joints or it WILL fatigue and fail.

RG58 is over kill and heavy to carry but use what you have. As you will be able to disconnect it, you can replace it with lightweight coax in the future. You don’t say which pole you are using but you probably need to attach RG58 to the upper sections of the pole so the pole doesn’t bend under the load.

The dipole calculator is great for getting in the zone quickly.
The MFJ will be easier to use than the VNA (especially at first) and will give just as good results.

Don’t use a PL259 unless you wish to be the focal point of derision :slight_smile:

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You don’t need a laptop/PC to use the NanoVNA as an antenna analyser. Just don’t do it on a sunny day or you won’t be able to see the screen.

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I agree but I think it is a a lot easier to use on a large screen. :slight_smile:

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Todays hint.

The PL259 is more robust. When the BNC falls apart, as they do, you get the last laugh.
I fill the back end (of the plug) with roof and gutter sealant to take the stress off the soldered connections.

73
Ron
VK3AFW.

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  1. Build all the bands you want from the start. Adding bands, in particular ones with shorter wavelengths, can be a very time consuming process.
  2. Start with the highest frequency band but have the ends strung out to roughly the same length as the final antenna will be. This will keep the angles the same as you progress to the lower bands.
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I second this. I didn’t build my dipole, I bought a 20/40 from SOTABeams. It didn’t take too long to regret not getting the 20/30/40.

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Hi John,

i build my Linked Dipole for 20 and 40 m self. Look at the Picture.

For Calibrate SWR i use an Nano VNA.

I use an Hyperflex 5 Cable. It ist very light an hase a very less attenuation. For further Question write me directly. The Antenna works very fine. Last Saturday i had an QSO with an VK Station.

73 Michael

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Hello Michael, excellent job with your self built linked dipole. Well done. :grinning:

73 de Geoff vk3sq

Thanks all.
I didn’t think RG58 was heavier than RG213.

I do have NanoVNA and also have connected it the PC, but I do need re-do the calibration.
Intend on using the 6m decathlon pole I have, support the weight of the 2m ladder line and coax OK if I mount on the 2nd telescopic section

I will add a connection to detach the coax from the centre section.(I might have a left over section from a G5RV with an SO239 attached)

@DC8yz - thanks for the offer.

Anyways, building the antenna will have to wait at least until next week. A full weekend at a round of the British GTs is where I am at this weekend on recovery duties.
Cheers
John
m0vaz

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RG 213: OD 10.3mm
RG 58: OD 5mm
RG174: OD 2.8mm

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I don’t know why I wrote rg213 in my comment…and no one picked me up on it. I meant to say RG174. Now edited.

No probs Fraser. :slight_smile: