Radio Preppers

General Category => Antennas => Topic started by: Sig Man on January 02, 2020, 08:30:35 AM

Title: End fed windom
Post by: Sig Man on January 02, 2020, 08:30:35 AM
Anyone tried this antenna design?
I know the article is in swedish, but i guess you get the idea.

https://radio.thulesius.se/wp-content/uploads/2017/08/qtc1303_Windom-antenn_sm0jzt_ver_02.pdf
Title: Re: End fed windom
Post by: Oliver on January 02, 2020, 04:27:52 PM
Hi Sig Man!
I am using that antenna/antenna style.
They are often called city windom antenna, because you just need one pole.
This can be a tree or a other house or whatever.

My is produced by:
https://www.radial.ru/catalog/antennas/dipole/windom6/eng/
The german importer is Wimo.

Its an exellent antenna.
I using it on 80 Meter a lot in FT8.
The reports i get are allways very good.
Most of the bands you don´t even need a tuner.
The build-in TXR tuners does the job anyhow.
These type of antenna will be also very good for fielddays or short time use.
(Oh yes it would be a solution for Gil)
My antenne came with a nice bag and has a exellent quality!

You see the rick on my qrz.com site.

73 de DO1OH
Oliver
Title: Re: End fed windom
Post by: gil on January 03, 2020, 05:44:05 AM
This antenna seems overly complicated compared to a simple 49:1 or 64:1 transformer...

Gil.
Title: Re: End fed windom
Post by: Oliver on January 03, 2020, 09:39:40 AM
Well Gil, the antenna is not that complicated to build as you see at the swedish PDF.

The advantages cannot be denied.
No tuner needed and you don´t have to care about ground connection.
The only disadvantage is the missing 30 and 15 Meter match.
Title: Re: End fed windom
Post by: Sig Man on January 03, 2020, 01:18:57 PM
Made one yesterday, used rg-174 for portable use. First attemp gave vswr 1.4 on 3.550, good on 7.050 and around 5 on 60m (the kx3 tuner will fix that).
Waiting for the snowstorm to end, so i can do a rx/tx test
Title: Re: End fed windom
Post by: gil on January 06, 2020, 05:45:11 AM
QuoteNo tuner needed and you don´t have to care about ground connection.

Same as an end-fed half-wave...

Gil.
Title: Re: End fed windom
Post by: Oliver on February 09, 2020, 05:04:48 PM
Quote from: gil on January 06, 2020, 05:45:11 AMSame as an end-fed half-wave...

Gil.

no matching needed on the most bands?


Title: Re: End fed windom
Post by: gil on February 10, 2020, 05:34:57 AM
Quoteno matching needed on the most bands?

Hi, correct. I am talking about a half-wave end-fed with a 49:1 transformer, not a random wire with a 9:1 UNUN. I have built a Windom, albeit not this exact design, with a dual-core Guanella BALUN. Because the two legs aren't the same length, even with the BALUN, I had RF stray currents problems... Actually, I've had troubles with random wires and any antenna that was not fed in the middle or half-waves at the end. Now, I only use dipoles or HWEFs, sometimes quarter-waves with radials, but I avoid antennas fed somewhere in between... Too much trouble...

Gil.
Title: Re: End fed windom
Post by: Lamewolf on November 02, 2020, 09:21:14 AM
I built a Windom, but I prefer the term "Off Center Fed Dipole" and I have no issues with RF because I also incorporated a good CMC choke in the same box with the 4:1 balun - works super good !  Initial resonance is set to 3.450 mhz to get 40, 20, 17, 12, 10, and 6 meters as close as possible, then I use a capacitor with a bleeder resistor across it for protection to move 80 meter resonance up the band without effecting the other bands.
Title: Re: End fed windom
Post by: gil on January 01, 2021, 02:26:27 PM
I've had much trouble with a Windom because of stray RF currents... Not so with a half-wave end-fed...

Gil.