{"product_id":"cha-80-short-ext","title":"CHA 80 SHORT EXT","description":"\u003cdiv class=\"product-technical-copy\"\u003e\n  \u003cp\u003e\u003cstrong\u003ePut 80\/75 meters into a site that cannot support the full 130 ft CHA LEFS 8010 wire.\u003c\/strong\u003e The CHA 80 SHORT EXT replaces the normal 67 ft 80-meter extension with a compact loaded Standard assembly approximately eight feet long.\u003c\/p\u003e\n\n  \u003cp\u003eThis is an accessory for the \u003ca href=\"\/products\/cha-lefs-8010-lightweight-end-fed-sloper-efhw\"\u003eCHA LEFS 8010\u003c\/a\u003e. It is not a standalone antenna and it does not replace the LEFS transformer or the 63 ft parent radiator.\u003c\/p\u003e\n\n  \u003ch2\u003eCurrent Standard production unit\u003c\/h2\u003e\n  \u003cp\u003eWe received 100 Standard units for the current production offer. Standard and PRO have identical electrical behavior; their difference is cosmetic. The product supplied by this page is the Standard construction shown in the current Standard documentation.\u003c\/p\u003e\n\n  \u003cdiv class=\"table-wrapper\"\u003e\u003ctable\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n\u003cth scope=\"row\"\u003eRequired parent antenna\u003c\/th\u003e\n\u003ctd\u003eCHA LEFS 8010\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003cth scope=\"row\"\u003eOverall accessory length\u003c\/th\u003e\n\u003ctd\u003e7 ft 11 in\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003cth scope=\"row\"\u003eStandard tail length\u003c\/th\u003e\n\u003ctd\u003e6 ft 11 in\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003cth scope=\"row\"\u003eLoading\u003c\/th\u003e\n\u003ctd\u003eFixed 120 uH series load after the 63 ft parent section\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003cth scope=\"row\"\u003eField-adjustable range\u003c\/th\u003e\n\u003ctd\u003e3.5-4.0 MHz\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003cth scope=\"row\"\u003eApproximate 2:1 bandwidth\u003c\/th\u003e\n\u003ctd\u003e80 kHz after adjustment\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003cth scope=\"row\"\u003eFactory starting point\u003c\/th\u003e\n\u003ctd\u003eApproximately 3.520 MHz\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003cth scope=\"row\"\u003eApproximate weight\u003c\/th\u003e\n\u003ctd\u003e7 oz\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\u003c\/div\u003e\n\n  \u003cp\u003e\u003cstrong\u003eImportant:\u003c\/strong\u003e 3.5-4.0 MHz is the range in which the resonant segment can be placed by adjusting the tuning stub. It does not mean one adjustment covers the entire 500 kHz allocation below 2:1 SWR.\u003c\/p\u003e\n\n  \u003ch2\u003eProduction SWR sweep\u003c\/h2\u003e\n  \u003cp\u003eThe September 25 production check reached approximately 1.45:1 near 3.50 MHz in the recorded installation. The full sweep also shows the parent LEFS 8010 system's higher-band responses. This is measured impedance at the analyzer reference plane for that setup—not a guaranteed curve for every installation. Height, ground, coax, nearby conductors, wire tension, and weather can move the result.\u003c\/p\u003e\n\n  \u003ch2\u003eInstallation and tuning\u003c\/h2\u003e\n  \u003col\u003e\n    \u003cli\u003eDeploy the documented 63 ft CHA LEFS 8010 section.\u003c\/li\u003e\n    \u003cli\u003eConnect the CHA 80 SHORT EXT at the extension point normally used by the 67 ft 80-meter wire.\u003c\/li\u003e\n    \u003cli\u003eUse the Standard coil-body strain-relief holes for the carabiners and the internal wing nuts for the electrical spade terminals. Tighten the wing nuts finger-tight.\u003c\/li\u003e\n    \u003cli\u003eSupport the low end approximately 3-5 ft above ground with some sag in the wire.\u003c\/li\u003e\n    \u003cli\u003eSweep 3.5-4.0 MHz at low power before trimming. If the intended frequency is already 2:1 or lower, stop.\u003c\/li\u003e\n    \u003cli\u003eTo move resonance upward, fold back or shorten only the tuning stub. Trim no more than one inch, restore the same geometry, and measure again.\u003c\/li\u003e\n  \u003c\/ol\u003e\n  \u003cp\u003eNever cut the loading coil or the 63 ft parent radiator. If the extension will not tune, remove it and verify the LEFS 8010 parent configuration near 7.075 MHz before changing the tail.\u003c\/p\u003e\n\n  \u003ch2\u003eGoverned 2D and interactive 3D NEC patterns\u003c\/h2\u003e\n  \u003cp\u003eTwo reviewed Standard models are available at 3.750 MHz. These are NEC simulation values for exact modeled geometries, not guaranteed installed gain.\u003c\/p\u003e\n  \u003cdiv class=\"table-wrapper\"\u003e\u003ctable\u003e\n    \u003cthead\u003e\u003ctr\u003e\n\u003cth scope=\"col\"\u003eConfiguration\u003c\/th\u003e\n\u003cth scope=\"col\"\u003eBand\u003c\/th\u003e\n\u003cth scope=\"col\"\u003eFrequency\u003c\/th\u003e\n\u003cth scope=\"col\"\u003ePeak NEC gain\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n\u003cth scope=\"row\"\u003eStandard sloper\u003c\/th\u003e\n\u003ctd\u003e80 m\u003c\/td\u003e\n\u003ctd\u003e3.750 MHz\u003c\/td\u003e\n\u003ctd\u003e-2.15 dBi\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003cth scope=\"row\"\u003eStandard horizontal\u003c\/th\u003e\n\u003ctd\u003e80 m\u003c\/td\u003e\n\u003ctd\u003e3.750 MHz\u003c\/td\u003e\n\u003ctd\u003e0.90 dBi\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\u003c\/div\u003e\n  \u003cp\u003e\u003ca href=\"\/pages\/chameleon-knowledge-base?tool=patterns\u0026amp;target=lefs-8010-short-ext#ckb-pattern-library\"\u003e\u003cstrong\u003eOpen the complete 2D and interactive 3D pattern library\u003c\/strong\u003e\u003c\/a\u003e\u003c\/p\u003e\n  \u003cp\u003eThe NEC model uses an ideal 120 uH series load. It does not include measured coil loss, transformer loss, feed-line current, installed mismatch, nearby structures, vegetation, real terrain, or field correlation. The measured SWR sweep and modeled radiation patterns answer different questions and must not be treated as interchangeable evidence.\u003c\/p\u003e\n\n  \u003ch2\u003eDocumentation\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0695\/0024\/0118\/files\/CHA_80_SHORT_EXT_User_Guide_260810.pdf?v=1786415564\" target=\"_blank\" rel=\"noopener\"\u003eCHA 80 SHORT EXT Operator's Manual\u003c\/a\u003e\u003c\/li\u003e\n    \u003cli\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0695\/0024\/0118\/files\/CHA_80_SHORT_EXT_Quick_Start_Standard_260810.pdf?v=1786415564\" target=\"_blank\" rel=\"noopener\"\u003eStandard Quick Start\u003c\/a\u003e\u003c\/li\u003e\n    \u003cli\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0695\/0024\/0118\/files\/CHA_80_SHORT_EXT_Standard_Flysheet_260810.pdf?v=1786415564\" target=\"_blank\" rel=\"noopener\"\u003eStandard flysheet\u003c\/a\u003e\u003c\/li\u003e\n    \u003cli\u003e\u003ca href=\"\/pages\/chameleon-knowledge-base?focus=ckb-efhw-handbook--cha-lefs-8010-standard#ckb-master-handbook\"\u003eCHA LEFS 8010 field guide in the Chameleon Knowledge Base\u003c\/a\u003e\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003cp\u003eThe Operator's Manual controls if a shorter document conflicts. Keep the complete antenna and supports clear of overhead power lines and public access. Use the lowest applicable power, duty-cycle, feed-line, connector, transformer, support, and completed-system limit.\u003c\/p\u003e\n\u003c\/div\u003e\n","brand":"Chameleon Antenna","offers":[{"title":"STANDARD","offer_id":51550215635190,"sku":null,"price":90.0,"currency_code":"USD","in_stock":true},{"title":"PRO","offer_id":51550215667958,"sku":null,"price":150.0,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0695\/0024\/0118\/files\/CHA_80_SHORT_EXT_001.jpg?v=1790368322","url":"https:\/\/chameleonantenna.com\/products\/cha-80-short-ext","provider":"Chameleon Antenna","version":"1.0","type":"link"}