Re: Resources mentioned regarding portable antennas
Gary Vaught - W9TIG
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Was unable to make the meeting, but am very grateful for the follow up!
Gary D Vaught
Gary D Vaught
We can engineer a solution to nearly any problem you can accurately define.
- somewhat anonymous
On Wed, Mar 11, 2020 at 7:20 AM Fred Dittrich <fdittric@...> wrote:
Your presentation gave us a rich source of devices for go packs. Thanks for sharing.
At 10:46 PM 3/10/2020, you wrote:
I mentioned a couple of resources at the meeting tonight.
Here are links to them.
â€œRandom Wire Lengthsâ€�
Good lengths in ft: 29 35.5 41 58 71 84 107 119 148 203 347 407 423
Trapped End Fed Half Wave Antennas
There are quite a few resources on the internet about trifilar winding a 9:1 transformer.
For the 9:1 and 49:1 transformers you can also wind a primary and secondary on the same core independently.
In the example below L1 (primary) has 3 turns and L2 at 9 turns. Ratio is 1:3, square that 3 and it is a 9:1 transformer. Could also easily wind a primary with 2 turns and secondary with 14 turns for EFHW (49:1).
Wired up ~17â€™ radiator and 6â€™ counterpoise. Kx3 had no trouble tuning it anywhere. Typically I use a 58â€™ radiator with 9:1 or the trapped EFHW.
The article about portable masts can be found here: http://www.4sqrp.com/4sqrpNewsLetter/201908.pdf
72/73 de Bryan, k0emt