The Double Zepp | The W3EDP | Longwire with MTFT |
Feeding the Double Zepp with Baluns |
Aperiodic antenna 10-40m | Vertical-L |
Feeding the Random Wire Double Zepp
The antenna left is a 2 x 13,5-m Double-Zepp at EA8/DK7ZB Fed with 14 m Wireman cable In the background is a monoband dipole as Inverted-Vee for 20 m |
The antenna is fed with a Transmatch-Tuner and Baluns 1:1 or 1:4 for the bands 40m and up
Ideal are capacitors with 350 pF,
here has the right C 140 pF, an additional plug-in-C has 100 pF, if the capacity is to low for tuning on any band. This box handles 700 Watts RF. |
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The input is fed with a current Balun, the output is connected optional to a Balun 1:1 or 1:4. In this case with the Double Zepp in EA8 I need the following combinations: |
40 m | Balun 1:1 with additional 100 pF |
30 m | Balun 1:4 |
20 m | Balun 1:4 with additional 100 pF |
17 m | Balun1:1 |
15 m | Balun 1:4 |
Balun 1:1 2x18 turns PTFE-cable bifilar on FT240-43, connected to the output socket of the Transmatch |
The Balun 1:4 on a FT240-43 can handle 1 KW. 2x8 turns PTFE-cable bifilar. Parallel to the input is a C with 12 pF/1KV for a better SWR (here made with 4x12pF/500V). In the input line is a current Balun with 9 turns of Aircell-5 coax-cable on FT240-43. Also good for 1 KW. Picture down. |
The Tuner with the current balun for the input and the output balun for the Wireman-cable