{"id":11044,"date":"2022-08-22T09:56:37","date_gmt":"2022-08-22T07:56:37","guid":{"rendered":"https:\/\/nolle.engineering\/?post_type=product&#038;p=11044"},"modified":"2026-05-05T23:48:03","modified_gmt":"2026-05-05T21:48:03","slug":"l-band-antenna-rhcp","status":"publish","type":"product","link":"https:\/\/nolle.engineering\/en\/product\/l-band-antenna-rhcp\/","title":{"rendered":"L-Band Inmarsat 1525 MHz"},"content":{"rendered":"<h2>What it does<\/h2>\n<p>A 3D-printed helix antenna tuned to the 1525\u20131559 MHz Inmarsat downlink band. Two form factors selectable at checkout:<\/p>\n<ul>\n<li><strong>3 turns, LHCP (default)<\/strong> \u2014 clips into a standard 40 mm LNB clamp on an offset satellite dish, ~50\u201380 cm. Best for stationary GEO reception of Inmarsat-3 \/ Inmarsat-4.<\/li>\n<li><strong>10 turns, RHCP (default)<\/strong> \u2014 direct reception on an el\/az rotor, no dish needed. Higher gain on low-elevation GEOs and suitable for both GEO and LEO satellites.<\/li>\n<\/ul>\n<p>Both variants share the same connector (N-type) and PETG construction. Polarization can be flipped on either form factor (LHCP \u2194 RHCP) at extra cost.<\/p>\n<h2>Specifications<\/h2>\n<table>\n<thead>\n<tr>\n<th>Parameter<\/th>\n<th>3-turn (offset dish)<\/th>\n<th>10-turn (direct)<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Center frequency<\/td>\n<td>1525 MHz<\/td>\n<td>1525 MHz<\/td>\n<\/tr>\n<tr>\n<td>Polarization (default)<\/td>\n<td>LHCP<\/td>\n<td>RHCP<\/td>\n<\/tr>\n<tr>\n<td>Helix turns<\/td>\n<td>3<\/td>\n<td>10<\/td>\n<\/tr>\n<tr>\n<td>Wire diameter<\/td>\n<td>3.5 mm<\/td>\n<td>3.5 mm<\/td>\n<\/tr>\n<tr>\n<td>Connector<\/td>\n<td>N-type<\/td>\n<td>N-type<\/td>\n<\/tr>\n<tr>\n<td>Length \u00d7 \u00d8<\/td>\n<td>186 \u00d7 180 mm<\/td>\n<td>521 \u00d7 180 mm<\/td>\n<\/tr>\n<tr>\n<td>Weight<\/td>\n<td>289 g<\/td>\n<td>650 g<\/td>\n<\/tr>\n<tr>\n<td>Mount<\/td>\n<td>Standard 40 mm LNB clamp<\/td>\n<td>6 \u00d7 M4 bolts (universal)<\/td>\n<\/tr>\n<tr>\n<td>Material<\/td>\n<td>PETG, UV-resistant<\/td>\n<td>PETG, UV-resistant<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h2>Measured performance<\/h2>\n<p>Live demonstration on the <a href=\"\/en\/websdr\/\">Inmarsat L-Band WebSDR<\/a> \u2014 receiving Inmarsat-4 (Alphasat) 25\u00b0E and Inmarsat-3 F5 54\u00b0W from grid square JN58UA using the 7-turn and 10-turn variants in production today.<\/p>\n<h2>Polarization &amp; dish use<\/h2>\n<p>The <strong>3-turn variant<\/strong> is designed for use as a <strong>dish feed<\/strong>. A parabolic reflector inverts the circular polarization on each reflection, so a 3-turn feed should be the <em>opposite<\/em> handedness of the desired received signal \u2014 pick LHCP if you need to receive RHCP off the dish, and vice versa. The <strong>10-turn variant<\/strong> is a standalone antenna with no dish, so feed polarization equals received signal polarization.<\/p>\n<h2>Typical use cases<\/h2>\n<ul>\n<li>Inmarsat STD-C and AERO message decoding (with JAERO + RTL-SDR \/ Airspy + L-band LNA)<\/li>\n<li>Iridium telemetry monitoring<\/li>\n<li>Mobile LEO downlink experiments (10-turn on rotor)<\/li>\n<\/ul>\n<h2>Compatible chain<\/h2>\n<ul>\n<li>L-band LNA (~+25 dB) \u2014 required since the antenna is passive<\/li>\n<li>SDR with at least 2 MHz bandwidth (RTL-SDR v3, Airspy Mini, or HackRF)<\/li>\n<li><a href=\"\/en\/product\/elevation_clamp\/\">Elevation clamp<\/a> + <a href=\"\/en\/product\/crossclamp\/\">Cross clamp<\/a> for a 40 mm pipe build<\/li>\n<li><a href=\"\/en\/product\/electronics_cover\/\">Electronics cover<\/a> for the LNA + SDR housing<\/li>\n<li><a href=\"\/en\/product\/tripod_mount\/\">Tripod adapter<\/a> for portable Manfrotto setup<\/li>\n<\/ul>\n<h2>Documented in the Lab<\/h2>\n<ul>\n<li><a href=\"\/en\/2024\/04\/05\/l-band-antenna-updates\/\">L-Band Antenna Updates<\/a> \u2014 design iteration notes<\/li>\n<li><a href=\"\/en\/2022\/10\/25\/l-band-websdr\/\">L-Band WebSDR<\/a> \u2014 public reception demo<\/li>\n<li><a href=\"\/en\/3d-printed-l-band-antenna\/\">Design narrative<\/a> \u2014 offset \/ prime focus \/ direct geometry comparison<\/li>\n<\/ul>\n<h2>Reviews &amp; demos<\/h2>\n<ul>\n<li><a href=\"https:\/\/www.youtube.com\/watch?v=aLsOZbsGJ1Q\">Tech Minds \u2014 L-Band Helix Antenna (3-turn LHCP with offset dish, YouTube)<\/a><\/li>\n<li><a href=\"https:\/\/www.youtube.com\/watch?v=D_qCCretwMA\">Tech Minds \u2014 High-Gain 10-Turn Helix For L-Band &amp; Inmarsat (YouTube)<\/a><\/li>\n<li><a href=\"https:\/\/www.rtl-sdr.com\/tech-minds-testing-an-inmarsat-l-band-helix-for-offset-satellite-dishes\/\">RTL-SDR.com \u2014 Testing an Inmarsat L-Band Helix for Offset Satellite Dishes<\/a><\/li>\n<\/ul>\n<p><em>Custom polarization or color combinations available on request \u2014 please use the contact form for a quote.<\/em><\/p>","protected":false},"excerpt":{"rendered":"<p>3D-printed L-band helix for Inmarsat reception (1525 MHz). Available as a 3-turn LHCP for offset-dish use or a 10-turn RHCP for direct reception with rotor \u2014 pick form factor + polarization at checkout. Original tuning, measured against Inmarsat-3 \/ Inmarsat-4 (Alphasat) downlinks.<\/p>","protected":false},"featured_media":12834,"template":"","meta":[],"product_brand":[],"product_cat":[52],"product_tag":[],"class_list":{"0":"post-11044","1":"product","2":"type-product","3":"status-publish","4":"has-post-thumbnail","6":"product_cat-lband","8":"first","9":"instock","10":"taxable","11":"shipping-taxable","12":"purchasable","13":"product-type-variable","14":"has-default-attributes"},"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v22.0 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>L-Band Inmarsat 1525 MHz \u2014 3D-printed helix antenna - nolle.engineering<\/title>\n<meta name=\"description\" content=\"3D-printed L-band helix for Inmarsat reception (1525 MHz). 3-turn LHCP for offset dish, or 10-turn RHCP for direct reception with rotor. Pick at checkout.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/nolle.engineering\/en\/product\/l-band-antenna-rhcp\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"L-Band Inmarsat 1525 MHz \u2014 3D-printed helix antenna - nolle.engineering\" \/>\n<meta property=\"og:description\" content=\"3D-printed L-band helix for Inmarsat reception (1525 MHz). 3-turn LHCP for offset dish, or 10-turn RHCP for direct reception with rotor. Pick at checkout.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/nolle.engineering\/en\/product\/l-band-antenna-rhcp\/\" \/>\n<meta property=\"og:site_name\" content=\"nolle.engineering\" \/>\n<meta property=\"article:modified_time\" content=\"2026-05-05T21:48:03+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/nolle.engineering\/wp-content\/uploads\/2022\/08\/7turns_1.png\" \/>\n\t<meta property=\"og:image:width\" content=\"1280\" \/>\n\t<meta property=\"og:image:height\" content=\"1024\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/png\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data1\" content=\"2 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\/\/nolle.engineering\/product\/l-band-antenna-rhcp\/\",\"url\":\"https:\/\/nolle.engineering\/product\/l-band-antenna-rhcp\/\",\"name\":\"L-Band Inmarsat 1525 MHz \u2014 3D-printed helix antenna - nolle.engineering\",\"isPartOf\":{\"@id\":\"https:\/\/nolle.engineering\/#website\"},\"datePublished\":\"2022-08-22T07:56:37+00:00\",\"dateModified\":\"2026-05-05T21:48:03+00:00\",\"description\":\"3D-printed L-band helix for Inmarsat reception (1525 MHz). 3-turn LHCP for offset dish, or 10-turn RHCP for direct reception with rotor. Pick at checkout.\",\"breadcrumb\":{\"@id\":\"https:\/\/nolle.engineering\/product\/l-band-antenna-rhcp\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/nolle.engineering\/product\/l-band-antenna-rhcp\/\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/nolle.engineering\/product\/l-band-antenna-rhcp\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Startseite\",\"item\":\"https:\/\/nolle.engineering\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Shop\",\"item\":\"https:\/\/nolle.engineering\/shop-archive\/\"},{\"@type\":\"ListItem\",\"position\":3,\"name\":\"L-Band Inmarsat 1525 MHz\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/nolle.engineering\/#website\",\"url\":\"https:\/\/nolle.engineering\/\",\"name\":\"nolle.engineering\",\"description\":\"explore \/ design \/ make\",\"publisher\":{\"@id\":\"https:\/\/nolle.engineering\/#organization\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/nolle.engineering\/?s={search_term_string}\"},\"query-input\":\"required name=search_term_string\"}],\"inLanguage\":\"en-US\"},{\"@type\":\"Organization\",\"@id\":\"https:\/\/nolle.engineering\/#organization\",\"name\":\"nolle.engineering\",\"url\":\"https:\/\/nolle.engineering\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/nolle.engineering\/#\/schema\/logo\/image\/\",\"url\":\"https:\/\/nolle.engineering\/wp-content\/uploads\/2026\/04\/ne-logo-white.png\",\"contentUrl\":\"https:\/\/nolle.engineering\/wp-content\/uploads\/2026\/04\/ne-logo-white.png\",\"width\":2311,\"height\":1480,\"caption\":\"nolle.engineering\"},\"image\":{\"@id\":\"https:\/\/nolle.engineering\/#\/schema\/logo\/image\/\"}}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"L-Band Inmarsat 1525 MHz \u2014 3D-printed helix antenna - nolle.engineering","description":"3D-printed L-band helix for Inmarsat reception (1525 MHz). 3-turn LHCP for offset dish, or 10-turn RHCP for direct reception with rotor. Pick at checkout.","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/nolle.engineering\/en\/product\/l-band-antenna-rhcp\/","og_locale":"en_US","og_type":"article","og_title":"L-Band Inmarsat 1525 MHz \u2014 3D-printed helix antenna - nolle.engineering","og_description":"3D-printed L-band helix for Inmarsat reception (1525 MHz). 3-turn LHCP for offset dish, or 10-turn RHCP for direct reception with rotor. Pick at checkout.","og_url":"https:\/\/nolle.engineering\/en\/product\/l-band-antenna-rhcp\/","og_site_name":"nolle.engineering","article_modified_time":"2026-05-05T21:48:03+00:00","og_image":[{"width":1280,"height":1024,"url":"https:\/\/nolle.engineering\/wp-content\/uploads\/2022\/08\/7turns_1.png","type":"image\/png"}],"twitter_card":"summary_large_image","twitter_misc":{"Est. reading time":"2 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/nolle.engineering\/product\/l-band-antenna-rhcp\/","url":"https:\/\/nolle.engineering\/product\/l-band-antenna-rhcp\/","name":"L-Band Inmarsat 1525 MHz \u2014 3D-printed helix antenna - nolle.engineering","isPartOf":{"@id":"https:\/\/nolle.engineering\/#website"},"datePublished":"2022-08-22T07:56:37+00:00","dateModified":"2026-05-05T21:48:03+00:00","description":"3D-printed L-band helix for Inmarsat reception (1525 MHz). 3-turn LHCP for offset dish, or 10-turn RHCP for direct reception with rotor. Pick at checkout.","breadcrumb":{"@id":"https:\/\/nolle.engineering\/product\/l-band-antenna-rhcp\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/nolle.engineering\/product\/l-band-antenna-rhcp\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/nolle.engineering\/product\/l-band-antenna-rhcp\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Startseite","item":"https:\/\/nolle.engineering\/"},{"@type":"ListItem","position":2,"name":"Shop","item":"https:\/\/nolle.engineering\/shop-archive\/"},{"@type":"ListItem","position":3,"name":"L-Band Inmarsat 1525 MHz"}]},{"@type":"WebSite","@id":"https:\/\/nolle.engineering\/#website","url":"https:\/\/nolle.engineering\/","name":"nolle.engineering","description":"explore \/ design \/ make","publisher":{"@id":"https:\/\/nolle.engineering\/#organization"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/nolle.engineering\/?s={search_term_string}"},"query-input":"required name=search_term_string"}],"inLanguage":"en-US"},{"@type":"Organization","@id":"https:\/\/nolle.engineering\/#organization","name":"nolle.engineering","url":"https:\/\/nolle.engineering\/","logo":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/nolle.engineering\/#\/schema\/logo\/image\/","url":"https:\/\/nolle.engineering\/wp-content\/uploads\/2026\/04\/ne-logo-white.png","contentUrl":"https:\/\/nolle.engineering\/wp-content\/uploads\/2026\/04\/ne-logo-white.png","width":2311,"height":1480,"caption":"nolle.engineering"},"image":{"@id":"https:\/\/nolle.engineering\/#\/schema\/logo\/image\/"}}]}},"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/nolle.engineering\/en\/wp-json\/wp\/v2\/product\/11044","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/nolle.engineering\/en\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/nolle.engineering\/en\/wp-json\/wp\/v2\/types\/product"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/nolle.engineering\/en\/wp-json\/wp\/v2\/media\/12834"}],"wp:attachment":[{"href":"https:\/\/nolle.engineering\/en\/wp-json\/wp\/v2\/media?parent=11044"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/nolle.engineering\/en\/wp-json\/wp\/v2\/product_brand?post=11044"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/nolle.engineering\/en\/wp-json\/wp\/v2\/product_cat?post=11044"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/nolle.engineering\/en\/wp-json\/wp\/v2\/product_tag?post=11044"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}