antennas:efhw

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antennas:efhw [2020/02/16 05:52] wx0mikantennas:efhw [2020/08/04 05:37] (current) – old revision restored (2020/04/21 05:56) wx0mik
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 ===== What bands does this cover? ===== ===== What bands does this cover? =====
  
-The 80m-10m (134' wire) version covers: 80m, 40m, 20m, 15m, 10m+The 80m-10m (134' wire) version covers: 80/40/30/20/17/15/12/10m
  
-The 40m-10m (67' wire) version covers: 40m, 20m, 15m, 10m+The 40m-10m (67' wire) version covers: 40/20/15/10m
  
 ===== 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 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. 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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 {{:antennas:screen_shot_2020-02-15_at_9.28.15_pm.png?direct&400|}} {{:antennas:screen_shot_2020-02-15_at_9.28.15_pm.png?direct&400|}}
  
-===== Full list of Materials =====+===== How do I put up this antenna? =====
  
-  * 3 - [[https://www.mouser.com/ProductDetail/Fair-Rite/5952003801?qs=jDkmxmCvr%252BQVSS7fXQNL%252BA%3D%3D|Mouser 623-5952003801]] +This is a very flexible antenna and it doesn't even require a counterpoise. Just ground it and you're good. 
-  * 14 gauge enameled wire + 
-  * 100-110 pf 5kv capacitor - [[https://www.ebay.com/itm/10Pcs-30KV-100P-100PF-101-high-voltage-ceramic-capacitor-30KVHFFS/264494440736?hash=item3d9518e120:g:D4EAAOSwls1cU~cl|10Pcs 30KV 100P 100PF 101 high voltage ceramic capacitor 30KVHFFS]] +Here are some examples: 
-  * 12-14 gauge insulated wire.+  * 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 ===== 
 + 
 +  * 3 - 52-mix torrids [[https://www.mouser.com/ProductDetail/Fair-Rite/5952003801?qs=jDkmxmCvr%252BQVSS7fXQNL%252BA%3D%3D|Mouser 623-5952003801]] 
 +  * ~8' - 12 gauge enameled wire 
 +  * 1100 pf 5kv capacitor - [[https://www.ebay.com/itm/10Pcs-30KV-100P-100PF-101-high-voltage-ceramic-capacitor-30KVHFFS/264494440736?hash=item3d9518e120:g:D4EAAOSwls1cU~cl|10Pcs 30KV 100P 100PF 101 high voltage ceramic capacitor 30KVHFFS]] 
 +  * 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
 +
 +{{:antennas:screen_shot_2020-02-16_at_12.00.25_am.png?direct&400|}}
 +
 +===== Can't I just buy one? =====
 +
 +Sure you can, check out [[https://myantennas.com/wp/product-category/antennas/efhw-multi-band/|MyAntennas]] that makes some good EFHW antennas.
 +
 +===== Where can I learn more? =====
 +  * There is a [[https://www.facebook.com/groups/EndFedHalfWaveAntennas/|Facebook group]] where the topic is this antenna where I got some of this information. I would start there.
 +
 +===== What does the patterns look like? =====
 +
 +  * [[https://www.qsl.net/kk4obi/EFHW%20Straight.html]]
 +
 +===== Where can I buy the parts? =====
 +
 +==== Ferrites ====
 +Here are a few sites that are known to have good ferrites:
 +
 +  * [[https://www.mouser.com/Passive-Components/EMI-Filters-EMI-Suppression/Ferrites/Ferrite-Toroids-Ferrite-Rings/_/N-bw7t9?P=1yxgw95Z1ymg4nr]]
 +  * [[http://www.amidoncorp.com/52-material-iron-powder-toroids/]]
 +
 +==== Capacitors ====
 +
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