Re: Resources mentioned regarding portable antennas

Gary Vaught - W9TIG

Was unable to make the meeting, but am very grateful for the follow up!

Best Regards,
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.


Fred AE0FD

At 10:46 PM 3/10/2020, you wrote:
I mentioned a couple of resources at the meeting tonight.

Here are links to them.

“Random Wire Lengths�

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 ~17’ radiator and 6’ counterpoise.  Kx3 had no trouble tuning it anywhere.  Typically I use a 58’ radiator with 9:1 or the trapped EFHW.

The article about portable masts can be found here:

72/73 de Bryan, k0emt



Gary Vaught

Join { to automatically receive all group messages.