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| antennas:efhw [2020/02/16 05:08] – wx0mik | antennas:efhw [2020/08/04 05:37] (current) – old revision restored (2020/04/21 05:56) wx0mik | ||
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| ====== End-Fed Half-Wave ====== | ====== End-Fed Half-Wave ====== | ||
| - | This is the page on the End-Fed Half-Wave antenna with a 49:1 transformer. This is a multiband antenna without the need for any tuner (which is the best type of antenna). With the blessing of Steve Ellington and his [[https:// | + | This is the page on the End-Fed Half-Wave antenna with a 49:1 transformer. This is a multiband antenna without the need for any tuner (which is the best type of antenna). With the blessing of Steve Ellington and his [[https:// |
| ===== What is an EFHW? ===== | ===== What is an EFHW? ===== | ||
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| ===== What bands does this cover? ===== | ===== What bands does this cover? ===== | ||
| - | The 80m-10m (134' wire) version covers: | + | The 80m-10m (134' wire) version covers: |
| - | The 40m-10m (67' wire) version covers: | + | The 40m-10m (67' wire) version covers: |
| ===== The Transformer ===== | ===== The Transformer ===== | ||
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| You can put a 2450 ohm non-inductive carbon resistor across the ground and antenna and put your SWR meter on it to see how it looks. It won't be the same as when you connect your antenna, but you can get an idea if you wired it correctly. | You can put a 2450 ohm non-inductive carbon resistor across the ground and antenna and put your SWR meter on it to see how it looks. It won't be the same as when you connect your antenna, but you can get an idea if you wired it correctly. | ||
| - | ===== The Wire ===== | + | ===== The Antenna |
| For 80m you need 134 feet of wire (not including the coil). For 40m you need 67' (not including the coil). For the coil, you need 6 turns on a 1" od PVC pipe. In both cases, you can use 12 or 14 AWG wire. | For 80m you need 134 feet of wire (not including the coil). For 40m you need 67' (not including the coil). For the coil, you need 6 turns on a 1" od PVC pipe. In both cases, you can use 12 or 14 AWG wire. | ||
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| {{: | {{: | ||
| - | ===== Full list of Materials | + | ===== 160m Modification |
| - | | + | In order to do this, you connect the center of your coax directly to the antenna and the ground of the coax directly to your ground. You need a good ground system to make this work well. |
| - | * 14 gauge enameled wire | + | |
| - | * 100-110 pf 5kv capacitor - [[https:// | + | This will add 160, 60, and 6. |
| - | * 12-14 gauge insulated wire. | + | |
| + | Here is how to set this up with a relay. | ||
| + | |||
| + | {{: | ||
| + | |||
| + | ===== 160m EFHW Antenna ===== | ||
| + | |||
| + | There are some changes if you want to do a 160m EFHW antenna. First, you need 260 feet of wire and no coil on the antenna. The transformer should be 3 - 43 mix cores with 3 primary and 21 secondary windings (up to 30 depending on SWR). Do not cross over the winding. Use a 200 pf capacitor instead of 100 pf. This is not as resonant on some of the other bands. | ||
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| + | {{: | ||
| + | |||
| + | ===== How do I put up this antenna? ===== | ||
| + | |||
| + | This is a very flexible antenna and it doesn' | ||
| + | |||
| + | Here are some examples: | ||
| + | * FullyHorizontal | ||
| + | * Inverted L configuration - Have a part of the antenna vertical and the rest horizontal. Keep the vertical part away from the house as it can pick up a lot of noise. | ||
| + | * Inverted V - No less than a 120-degree angle | ||
| + | * Fully vertical | ||
| + | |||
| + | I have heard stories of bends, weaves, and other not-so-common configurations and it works for them. It can be used for portable or permanent. It's a really good all-around antenna. | ||
| + | |||
| + | ===== Full list of Materials for 80-10 version ===== | ||
| + | |||
| + | | ||
| + | * ~8' - 12 gauge enameled wire | ||
| + | * 1- 100 pf 5kv capacitor - [[https:// | ||
| + | * 134' + coil - 12-14 gauge insulated wire | ||
| * 1 inch piece of 1" OD PVC pipe | * 1 inch piece of 1" OD PVC pipe | ||
| * Stainless Steel bolts, nuts, washers, and eye bolts. | * Stainless Steel bolts, nuts, washers, and eye bolts. | ||
| + | * Enclosure | ||
| + | * Vent | ||
| + | |||
| + | {{: | ||
| + | |||
| + | ===== Can't I just buy one? ===== | ||
| + | |||
| + | Sure you can, check out [[https:// | ||
| + | |||
| + | ===== Where can I learn more? ===== | ||
| + | * There is a [[https:// | ||
| + | |||
| + | ===== What does the patterns look like? ===== | ||
| + | |||
| + | * [[https:// | ||
| + | |||
| + | ===== Where can I buy the parts? ===== | ||
| + | |||
| + | ==== Ferrites ==== | ||
| + | Here are a few sites that are known to have good ferrites: | ||
| + | |||
| + | * [[https:// | ||
| + | * [[http:// | ||
| + | |||
| + | ==== Capacitors ==== | ||
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