{"id":6510,"date":"2026-03-09T16:47:46","date_gmt":"2026-03-09T21:47:46","guid":{"rendered":"https:\/\/www.summet.com\/blog\/?p=6510"},"modified":"2026-03-11T13:57:24","modified_gmt":"2026-03-11T18:57:24","slug":"creating-a-usdx-all-in-one-cable-aioc-using-the-k1-connect-open-hardware-board-from-na6d","status":"publish","type":"post","link":"https:\/\/www.summet.com\/blog\/2026\/03\/09\/creating-a-usdx-all-in-one-cable-aioc-using-the-k1-connect-open-hardware-board-from-na6d\/","title":{"rendered":"Building a uSDX+ all in one cable (AIOC) using the K1-Connect open hardware board from NA6D"},"content":{"rendered":"<p><iframe loading=\"lazy\" title=\"YouTube video player\" src=\"https:\/\/www.youtube-nocookie.com\/embed\/1dn3_DAmoso?si=ORhNIOwr3xdL6HVN\" width=\"560\" height=\"315\" frameborder=\"0\" allowfullscreen=\"allowfullscreen\"><\/iframe><\/p>\n<p><a href=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/3-prongs-on-table.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-large wp-image-6525\" src=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/3-prongs-on-table-1024x576.jpg\" alt=\"\" width=\"584\" height=\"329\" srcset=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/3-prongs-on-table-1024x576.jpg 1024w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/3-prongs-on-table-300x169.jpg 300w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/3-prongs-on-table-768x432.jpg 768w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/3-prongs-on-table-1536x864.jpg 1536w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/3-prongs-on-table-2048x1152.jpg 2048w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/3-prongs-on-table-500x281.jpg 500w\" sizes=\"auto, (max-width: 584px) 100vw, 584px\" \/><\/a><\/p>\n<p><a href=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/encased-in-resin-16x9-1-scaled.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-large wp-image-6511\" src=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/encased-in-resin-16x9-1-1024x576.jpg\" alt=\"\" width=\"584\" height=\"329\" srcset=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/encased-in-resin-16x9-1-1024x576.jpg 1024w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/encased-in-resin-16x9-1-300x169.jpg 300w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/encased-in-resin-16x9-1-768x432.jpg 768w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/encased-in-resin-16x9-1-1536x864.jpg 1536w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/encased-in-resin-16x9-1-2048x1152.jpg 2048w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/encased-in-resin-16x9-1-500x281.jpg 500w\" sizes=\"auto, (max-width: 584px) 100vw, 584px\" \/><\/a><\/p>\n<p>I added a 3rd 3.5mm plug to the open hardware <a href=\"https:\/\/na6d.com\/products\/aioc-ham-radio-all-in-one-cable\">AIOC sold by NA6D<\/a> to send the serial data to the CAT port on my <a href=\"https:\/\/www.ebay.com\/itm\/357131566702\">uSDX+<\/a> SDR radio.<\/p>\n<p><!--more--><br \/>\n<a href=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/wires-top-scaled.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-large wp-image-6527\" src=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/wires-top-1024x576.jpg\" alt=\"\" width=\"584\" height=\"329\" srcset=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/wires-top-1024x576.jpg 1024w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/wires-top-300x169.jpg 300w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/wires-top-768x432.jpg 768w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/wires-top-1536x864.jpg 1536w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/wires-top-2048x1152.jpg 2048w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/wires-top-500x281.jpg 500w\" sizes=\"auto, (max-width: 584px) 100vw, 584px\" \/><\/a><\/p>\n<p><a href=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/wires-bottom-scaled.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-large wp-image-6528\" src=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/wires-bottom-1024x576.jpg\" alt=\"\" width=\"584\" height=\"329\" srcset=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/wires-bottom-1024x576.jpg 1024w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/wires-bottom-300x169.jpg 300w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/wires-bottom-768x432.jpg 768w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/wires-bottom-1536x864.jpg 1536w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/wires-bottom-2048x1152.jpg 2048w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/wires-bottom-500x281.jpg 500w\" sizes=\"auto, (max-width: 584px) 100vw, 584px\" \/><\/a><\/p>\n<p>The stock AIOC works fine for Audio In\/Out and Push To Talk (via DTR line on the serial port). So you can use it for FT8 or other digital modes on the uSDX+ radio (or anything else that uses a Kenwood style 2.5mm &amp; 3.5mm dual jack). However, without CAT control, you have to manually set the frequency (which isn&#8217;t difficult, but on the uSDX+ with the minimal UI elements, it&#8217;s also not easy).<\/p>\n<p><a href=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/AIOC-full-pinout.png\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-6512\" src=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/AIOC-full-pinout.png\" alt=\"\" width=\"834\" height=\"918\" srcset=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/AIOC-full-pinout.png 834w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/AIOC-full-pinout-273x300.png 273w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/AIOC-full-pinout-768x845.png 768w\" sizes=\"auto, (max-width: 834px) 100vw, 834px\" \/><\/a><\/p>\n<p>The main difficulty with this addition is that the stock AIOC from NA6D has the PTT and TXD pads &#8220;merged&#8221;, which works fine for programing a Baofeng HT before you use it, but results in the uSDX+ changing into transmit mode every time the CAT control tries to do anything such as read the current frequency every second. So I had to use a dremel tool with a cutting wheel to split the ground connection from the 3.5mm plug so that I could separate the PTT side of things (which I wanted to keep attached there) from the TXD pin (which I want on my own new 3.5mm plug for the CAT port).<br \/>\n<a href=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/cut-with-dremel-scaled.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-large wp-image-6513\" src=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/cut-with-dremel-1024x576.jpg\" alt=\"\" width=\"584\" height=\"329\" srcset=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/cut-with-dremel-1024x576.jpg 1024w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/cut-with-dremel-300x169.jpg 300w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/cut-with-dremel-768x432.jpg 768w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/cut-with-dremel-1536x864.jpg 1536w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/cut-with-dremel-2048x1152.jpg 2048w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/cut-with-dremel-500x281.jpg 500w\" sizes=\"auto, (max-width: 584px) 100vw, 584px\" \/><\/a><\/p>\n<p>I was able to simply wire up a direct connection to the RXD pad without having to edit anything on the main circuit, as the uSDX+ doesn&#8217;t mess with that particular ring on the 2.5mm plug.<\/p>\n<p>Because the AIOC doesn&#8217;t have pads to physically solder a 3rd plug in the right spot for the uSDX+ CAT jack, I used UV Cured Resin to hold the new plug physically in place, and then cut the original 3D printed plastic case around the new addition.<\/p>\n<p><a href=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/case-on-uv-resin-showing.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-large wp-image-6526\" src=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/case-on-uv-resin-showing-1024x576.jpg\" alt=\"\" width=\"584\" height=\"329\" srcset=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/case-on-uv-resin-showing-1024x576.jpg 1024w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/case-on-uv-resin-showing-300x169.jpg 300w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/case-on-uv-resin-showing-768x432.jpg 768w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/case-on-uv-resin-showing-1536x864.jpg 1536w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/case-on-uv-resin-showing-2048x1152.jpg 2048w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/case-on-uv-resin-showing-500x281.jpg 500w\" sizes=\"auto, (max-width: 584px) 100vw, 584px\" \/><\/a><\/p>\n<p>The uSDX+ radio (a Chinese clone of an early (tr) uSDX radio, performs relatively well, but I&#8217;ve found that the firmware support for CAT control isn&#8217;t 100%.\u00a0 Simple things like reading and setting the frequency work fine, as does RX\/TX control via CAT.\u00a0 But at least with WSJTX, I found that the &#8220;fake it&#8221; frequency shifting didn&#8217;t work correctly (in that it would move up to a new frequency when transmitting, but not move back down when it finished transmitting, leading to your frequency creeping out of band entirely over several 15-second cycles).<br \/>\nHowever, the range achievable with only 4-5 watts in FT8 Digital mode with a good antenna is still impressive.<\/p>\n<p><a href=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/Who-can-hear-me-at-5-watts-20m-night-16x9-1.png\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-large wp-image-6516\" src=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/Who-can-hear-me-at-5-watts-20m-night-16x9-1-1024x576.png\" alt=\"\" width=\"584\" height=\"329\" srcset=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/Who-can-hear-me-at-5-watts-20m-night-16x9-1-1024x576.png 1024w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/Who-can-hear-me-at-5-watts-20m-night-16x9-1-300x169.png 300w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/Who-can-hear-me-at-5-watts-20m-night-16x9-1-768x432.png 768w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/Who-can-hear-me-at-5-watts-20m-night-16x9-1-500x281.png 500w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/Who-can-hear-me-at-5-watts-20m-night-16x9-1.png 1224w\" sizes=\"auto, (max-width: 584px) 100vw, 584px\" \/><\/a> <a href=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/Who-can-hear-me-at-5-watts-40m-night-even-better-16x9-1.png\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-large wp-image-6517\" src=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/Who-can-hear-me-at-5-watts-40m-night-even-better-16x9-1-1024x576.png\" alt=\"\" width=\"584\" height=\"329\" srcset=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/Who-can-hear-me-at-5-watts-40m-night-even-better-16x9-1-1024x576.png 1024w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/Who-can-hear-me-at-5-watts-40m-night-even-better-16x9-1-300x169.png 300w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/Who-can-hear-me-at-5-watts-40m-night-even-better-16x9-1-768x432.png 768w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/Who-can-hear-me-at-5-watts-40m-night-even-better-16x9-1-500x281.png 500w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2026\/03\/Who-can-hear-me-at-5-watts-40m-night-even-better-16x9-1.png 1367w\" sizes=\"auto, (max-width: 584px) 100vw, 584px\" \/><\/a><\/p>\n<p>If you are looking to replicate this project, I&#8217;d strongly suggest starting with a <a href=\"https:\/\/na6d.com\/products\/aioc-ham-radio-all-in-one-cable-unsoldered\">AIOC kit that doesn&#8217;t have the plugs already soldered on<\/a>, as at least half of my effort was splitting out the PTT and TXD pads.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>I added a 3rd 3.5mm plug to the open hardware AIOC sold by NA6D to send the serial data to the CAT port on my uSDX+ SDR radio.<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[13],"tags":[162,166],"class_list":["post-6510","post","type-post","status-publish","format-standard","hentry","category-projects","tag-ham","tag-usdx"],"_links":{"self":[{"href":"https:\/\/www.summet.com\/blog\/wp-json\/wp\/v2\/posts\/6510","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.summet.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.summet.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.summet.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.summet.com\/blog\/wp-json\/wp\/v2\/comments?post=6510"}],"version-history":[{"count":8,"href":"https:\/\/www.summet.com\/blog\/wp-json\/wp\/v2\/posts\/6510\/revisions"}],"predecessor-version":[{"id":6530,"href":"https:\/\/www.summet.com\/blog\/wp-json\/wp\/v2\/posts\/6510\/revisions\/6530"}],"wp:attachment":[{"href":"https:\/\/www.summet.com\/blog\/wp-json\/wp\/v2\/media?parent=6510"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.summet.com\/blog\/wp-json\/wp\/v2\/categories?post=6510"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.summet.com\/blog\/wp-json\/wp\/v2\/tags?post=6510"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}