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mission:log:2012:08:02:active-wideband-receiver-antenna-for-sdr [2015/09/16 13:28]
chrono [Ultra-Cheap LNA alternatives]
mission:log:2012:08:02:active-wideband-receiver-antenna-for-sdr [2017/01/04 23:32] (current)
chrono [Antenna Element]
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 ==== Antenna Element ==== ==== Antenna Element ====
  
-The antenna element itself is a simple quadrilateral monopole, in the shape of a wedge, with a narrow start and a wider end. For lack of a common nomenclature and a relatively close optical proximity to a log-per design, this type is going to be ignorantly called //​log-per-spiral//​. The monopole is "​glued"​ onto a self-adhesive,​ semirigid, matte-white material and then rolled to a cylinder with 80mm diameter, thus forming a spiral. Unfortunately,​ there seems virtually no accessible background data available about the RF properties of this particular antenna design. A NEC simulation would be interesting.+The antenna element itself is a simple quadrilateral monopole, in the shape of a wedge, with a narrow start and a wider end. For lack of a common nomenclature and a relatively close optical proximity to a log-per design, this type is going to be ignorantly called //​log-per-spiral//​. The monopole is "​glued"​ onto a self-adhesive,​ semirigid, matte-white material and then rolled to a cylinder with 80mm diameter, thus forming a spiral. Unfortunately,​ there seems virtually no accessible background data available about the RF properties of this particular antenna design. ​
  
-[{{:​lab:​awra-antenna-element1.png?​186|Copp +[{{:​lab:​awra-antenna-element1.png?​186|Copper ​Antenna Element}}]
-er Antenna Element}}]+
 [{{:​lab:​awra-antenna-element-with-pvc-foil.png?​186|Antenna Element placed}}] [{{:​lab:​awra-antenna-element-with-pvc-foil.png?​186|Antenna Element placed}}]
 [{{:​lab:​active-wideband-receiver-antenna-original-unrolled.jpg?​188|Original unrolled}}] [{{:​lab:​active-wideband-receiver-antenna-original-unrolled.jpg?​188|Original unrolled}}]
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 ~~CL~~ ~~CL~~
 \\ \\
-The small start of the original copper log-per-spiral begins at a 25mm offset from the bottom part of the white, rolled 80mm cylinder, the wider end extends 75mm over the upper edge. After 55mm from the edge of the white cylinder, the rest of the copper is bent around the outer tube and then covered by the cap. This has probably no effect on RF properties (can someone verify this?) but is probably a way to give the whole structure more mechanical support.+The small start of the original copper log-per-spiral begins at a 25mm offset from the bottom part of the white, rolled 80mm cylinder, the wider end extends 75mm over the upper edge. After 55mm from the edge of the white cylinder, the rest of the copper is bent around the outer tube and then covered by the cap. This has probably no effect on RF properties (can someone verify this?) but is probably a way to give the whole structure more mechanical support. ​ 
 + 
 +For easier replication,​ use one of the following cutting helper templates:
  
 <WRAP round download>​ <WRAP round download>​
 **Downloads:​**\\ **Downloads:​**\\
-[[https://​apollo.open-resource.org/​downloads/​active-wideband-receiver-antenna-cutting-helper-V1.0.svg|Copper Element Cutting helper (1:1)]]\\+{{:​mission:​log:​2012:​08:​02:​dressler-ara-2000-wide-band-antenna-split.pdf|Split-Print DIN A4 Copper-Element ​ Cutting Helper by Dave (recommended)}}\\ 
 +[[https://​apollo.open-resource.org/​downloads/​active-wideband-receiver-antenna-cutting-helper-V1.0.svg|Original ​Copper-Element Cutting helper ​draft(1:1)]]\\
 </​WRAP>​ </​WRAP>​
 === Properties === === Properties ===
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 [[http://​www.gpe-shop.de/​index.php/​kappen/​kappen-fur-rundrohre/​kappen-fur-rundrohre/​k-serie/​pvc-kappen-fur-rr-weiss/​k-90-w.html|Caps]] [[http://​www.gpe-shop.de/​index.php/​kappen/​kappen-fur-rundrohre/​kappen-fur-rundrohre/​k-serie/​pvc-kappen-fur-rr-weiss/​k-90-w.html|Caps]]
  
 +==== NEC2 Simulation ====
 +
 +First NEC2 Simulation efforts by Samuel Burri: ​
 +
 +{{:​mission:​log:​2012:​08:​02:​ara_2000_xnec2c.png|XNEC2 ARA-2000 Simulation}}
 +
 +https://​www.samuelburri.ch/​2016/​06/​10/​ara-2000-antenna-model/​
 ===== LNA ===== ===== LNA =====