{"id":146,"date":"2019-08-09T12:23:06","date_gmt":"2019-08-09T02:23:06","guid":{"rendered":"http:\/\/www.vk1zdj.net\/?p=146"},"modified":"2019-08-09T15:20:10","modified_gmt":"2019-08-09T05:20:10","slug":"mchf-clones-from-china","status":"publish","type":"post","link":"http:\/\/www.vk1zdj.net\/?p=146","title":{"rendered":"mcHF clones from China"},"content":{"rendered":"

 <\/p>\n

So much has happened in the time since I last posted – I have moved house (and workshop), changed employers, etc, etc, and not been in a position to do much SOTA work, but thats ok – At least I have this amazing hobby to keep me happily engaged in technology.<\/p>\n

A while ago I brought an interesting SDR HF radio from eBay.\u00a0 It turned out that it was a copy of an awesome project called mcHF, developed by M0NKA.\u00a0 There is a heap of bad press about these radios, as the Chinese distributors simply copied M0NKA’s 0.4 version of his open source project, which is not helpful at all.<\/p>\n

I have sent an email to Chris about either purchasing an 0.6 version of his boardset to allow me to contribute to the project, or simply making a ‘licence’ payment to ensure that he benefits from those of us who made an error.<\/p>\n

In any case, I have a really neat little radio that is in an unknown state.<\/p>\n

What an awesome ‘fixer upper’ \ud83d\ude42<\/p>\n

So – Firstly, Chris identified a couple of problems when he posted about the clones in September 2017;<\/p>\n

    \n
  1. The sampling capacitors in exciter and detector are not the correct type –\n
      \n
    1. (C84, C85, C86, C87) Exciter\u00a0 \u00a0Farnel\u00a0221-1120<\/li>\n
    2. (C68,C69) Detector\u00a0 Farnel\u00a0221-1120<\/li>\n<\/ol>\n<\/li>\n
    3. The PA Bias circuit may be incorrect.<\/li>\n
    4. The use of Multi Layer inductors in the BPFs was identified as wrong by Chris\n
        \n
      1. L1 – 2.2uH\u00a0Farnel 166-9889<\/li>\n
      2. L2 – 1uH Farnel\u00a0166-9882<\/li>\n
      3. L3 – 0.47uH\u00a0Farnel 166-9913<\/li>\n
      4. L4 – 0.33uH Farnel\u00a0166-9911<\/li>\n
      5. L5 – 4.7uH Farnel\u00a0166-9896<\/li>\n
      6. L6 – 2.2uH Farnel\u00a0166-9889<\/li>\n
      7. L7 – 1uH Farnel\u00a0166-9882<\/li>\n
      8. L8 – 0.68uH Farnel\u00a0166-9915<\/li>\n
      9. L9 – 2.2uH Farnel 166-9889<\/li>\n
      10. L10 – 1uH Farnel\u00a0166-9882<\/li>\n
      11. L11 – 0.47uH Farnel\u00a0166-9913<\/li>\n
      12. L12 – 0.33uH Farnel\u00a0166-9911<\/li>\n<\/ol>\n<\/li>\n<\/ol>\n

        I will sweep the Bandass filters before I replace the indicuors so that I can identify how much of an issue the use of incorrect inductors actually was.<\/p>\n

        In summary, for the next couple of months, I think I will tear down the radio and spend some effort on identifying the changes between what this boardset actually is, and what I need to do to bring it up to spec based on the mcHF errata pages.<\/p>\n

        I shall keep you updated.<\/p>\n","protected":false},"excerpt":{"rendered":"

          So much has happened in the time since I last posted – I have moved house (and workshop), changed employers, etc, etc, and not been in a position to do much SOTA work, but thats ok –… <\/p>\n","protected":false},"author":1,"featured_media":148,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"inline_featured_image":false},"categories":[6],"tags":[],"jetpack_featured_media_url":"http:\/\/www.vk1zdj.net\/wp-content\/uploads\/2019\/08\/mcHF.jpg","_links":{"self":[{"href":"http:\/\/www.vk1zdj.net\/index.php?rest_route=\/wp\/v2\/posts\/146"}],"collection":[{"href":"http:\/\/www.vk1zdj.net\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.vk1zdj.net\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.vk1zdj.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.vk1zdj.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=146"}],"version-history":[{"count":6,"href":"http:\/\/www.vk1zdj.net\/index.php?rest_route=\/wp\/v2\/posts\/146\/revisions"}],"predecessor-version":[{"id":153,"href":"http:\/\/www.vk1zdj.net\/index.php?rest_route=\/wp\/v2\/posts\/146\/revisions\/153"}],"wp:featuredmedia":[{"embeddable":true,"href":"http:\/\/www.vk1zdj.net\/index.php?rest_route=\/wp\/v2\/media\/148"}],"wp:attachment":[{"href":"http:\/\/www.vk1zdj.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=146"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.vk1zdj.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=146"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.vk1zdj.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=146"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}