{"id":5726,"date":"2016-08-21T11:25:00","date_gmt":"2016-08-21T01:25:00","guid":{"rendered":"https:\/\/www.homebrewradio.us\/blog\/2016\/08\/21\/first-signals-from-the-pa3gsv-mighty-midget-mate\/"},"modified":"2016-08-21T11:25:00","modified_gmt":"2016-08-21T01:25:00","slug":"first-signals-from-the-pa3gsv-mighty-midget-mate","status":"publish","type":"post","link":"https:\/\/www.homebrewradio.us\/blog\/2016\/08\/21\/first-signals-from-the-pa3gsv-mighty-midget-mate\/","title":{"rendered":"First Signals from the PA3GSV Mighty Midget Mate"},"content":{"rendered":"<p><iframe loading=\"lazy\" allowfullscreen=\"\" frameborder=\"0\" height=\"248\" src=\"https:\/\/www.youtube.com\/embed\/CMQDYpZRkPw?rel=0\" width=\"440\"><\/iframe>  <\/p>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2448\"> <span lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><br \/><\/span> <span lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><i><b>Obviously the Radio Gods (Spirits in the Sky) approve of Jan&#8217;s work. How could they not? I can now see why he took the trouble to cut that hole in the sewer pipe cap that forms the large wheel on his homebrew reduction drive. But what are we going to see through that center hole Jan? What will the frequency readout be like? <\/b><\/i><\/span><br \/> <span lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;-<\/b><\/span><br \/> <b style=\"color: #1f497d; font-family: calibri, sans-serif; font-size: 11pt;\">Hi Bill,<\/b><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2454\"> <b><br \/><\/b><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2456\"> <span id=\"yui_3_16_0_ym19_1_1471777614115_2455\" lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>Just finished the last stage of the Mighty Midget MK2.<\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2467\"> <span id=\"yui_3_16_0_ym19_1_1471777614115_2466\" lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>There are first signals!<\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2469\"> <span id=\"yui_3_16_0_ym19_1_1471777614115_2468\" lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>The first one I heard was a broadcast station, believe it or not, the song that was on was \u201cSpirit in the Sky\u201d ..<\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2470\"> <b style=\"color: #1f497d; font-family: calibri, sans-serif; font-size: 11pt;\">All stages were built, tested and as far as possible, adjusted separately.<\/b><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2472\"> <span id=\"yui_3_16_0_ym19_1_1471777614115_2471\" lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>It was built from back to front, so the RF amplifier was last.<\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2474\"> <span id=\"yui_3_16_0_ym19_1_1471777614115_2473\" lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>I added an ECL82 for more audio, the first thought of only using an EL84 didn\u2019t bring enough.<\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\"> <span lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>The triode of the ECL82 as a pre-amp, the pentode as final.<\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\"> <span lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>Furthermore ECF82\u2019s were used instead of the 6U8, they\u2019re more widely available over here.<\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2476\"> <span id=\"yui_3_16_0_ym19_1_1471777614115_2475\" lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>The Miller coils are hard to come by, so the 300 uH coils are homebrew.<\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2478\"> <span id=\"yui_3_16_0_ym19_1_1471777614115_2477\" lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>Also used a grid detector instead of the two germanium diodes.<\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\"> <span lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>The triode of V1 originally intended for audio was used for this.<\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2480\"> <b><span id=\"yui_3_16_0_ym19_1_1471777614115_2479\" lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\">Made the BFO adjustable as well, still remember the screwdriver sticking out of the coil on your side&#8230;<\/span><span lang=\"EN-US\" style=\"color: #1f497d; font-family: \"wingdings\"; font-size: 11.0pt;\"> <\/span><span lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><\/span><\/b><\/div>\n<div class=\"yiv9079190982MsoNormal\"> <span lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b> <\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2517\"> <span id=\"yui_3_16_0_ym19_1_1471777614115_2516\" lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>Happily there was not much troubleshooting needed.<\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2482\"> <span id=\"yui_3_16_0_ym19_1_1471777614115_2481\" lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>The 80m coil was only 5 kHz off, the 40m coil 300 kHz (to low in frequency), still have to fix that.<\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2515\"> <span id=\"yui_3_16_0_ym19_1_1471777614115_2514\" lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>Initially the receiver worked reasonably well without adjusting, but C1 quit at some point.<\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2484\"> <span id=\"yui_3_16_0_ym19_1_1471777614115_2483\" lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>After some investigation, the problem was a dirty wiper contact on the rotor.<\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2486\"> <span id=\"yui_3_16_0_ym19_1_1471777614115_2485\" lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>An ultrasonic bath fixed the problem, so no looking out for a replacement there. (hope it stays that way)<\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2487\"> <span lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b> <\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2489\"> <span id=\"yui_3_16_0_ym19_1_1471777614115_2488\" lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>After adjusting, sensitivity is around -114dBm (0,4 uV) \/ 10 dB S\/N! (with the FT241 crystals in place, and careful tuning of the controls)<\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2513\"> <span id=\"yui_3_16_0_ym19_1_1471777614115_2512\" lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>Really not bad for this small receiver, Lew McCoy was right, it really is a Mighty Midget.<\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2505\"> <span id=\"yui_3_16_0_ym19_1_1471777614115_2504\" lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>I wanted to make some video\u2019s, but over here there\u2019s a terrible S9 rattle from 160 to 15 meters.<\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2503\"> <span id=\"yui_3_16_0_ym19_1_1471777614115_2502\" lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>Every now and then it appears out of nowhere, and disappears the same way.<\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2511\"> <span id=\"yui_3_16_0_ym19_1_1471777614115_2510\" lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>As soon as it is gone, I\u2019ll make some video\u2019s.<\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2501\"> <span id=\"yui_3_16_0_ym19_1_1471777614115_2500\" lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>I made one video though, just after completing the receiver.<\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2499\"> <span lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b> <\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2509\"> <span id=\"yui_3_16_0_ym19_1_1471777614115_2508\" lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><a href=\"https:\/\/www.youtube.com\/watch?v=CMQDYpZRkPw\" id=\"yui_3_16_0_ym19_1_1471777614115_2507\" rel=\"nofollow\" target=\"_blank\"><b>https:\/\/www.youtube.com\/watch?v=CMQDYpZRkPw<\/b><\/a><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\"> <span lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b> <\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2498\"> <span id=\"yui_3_16_0_ym19_1_1471777614115_2497\" lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>Reception on CW and SSB sounds really well, but unfortunately didn\u2019t record that.<\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2490\"> <span lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>The receiver is not finished yet.<\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\"> <span lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>Next to the 40m coil, S-meter has to be tried, and there\u2019s still some work on the cabinet and front panel.<\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\"> <span lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b> <\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2496\"> <span lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>More to follow.<\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2493\"> <span lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b> <\/b><\/span><b style=\"color: #1f497d; font-family: calibri, sans-serif; font-size: 11pt;\"> <\/b><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2491\"> <span lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>73 Jan<\/b><\/span><\/div>\n<div class=\"yiv9079190982MsoNormal\" id=\"yui_3_16_0_ym19_1_1471777614115_2494\"> <span lang=\"EN-US\" style=\"color: #1f497d; font-family: \"calibri\" , sans-serif; font-size: 11.0pt;\"><b>PA3GSV<\/b><\/span><\/div>\n","protected":false},"excerpt":{"rendered":"<p>Obviously the Radio Gods (Spirits in the Sky) approve of Jan&#8217;s work. How could they not? I can now see why he took the trouble to cut that hole in the sewer pipe cap that forms the large wheel on his homebrew reduction drive. But what are we going to see through that center hole &hellip; <a href=\"https:\/\/www.homebrewradio.us\/blog\/2016\/08\/21\/first-signals-from-the-pa3gsv-mighty-midget-mate\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;First Signals from the PA3GSV Mighty Midget Mate&#8221;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[200,262,166,101],"tags":[],"class_list":["post-5726","post","type-post","status-publish","format-standard","hentry","category-mate-for-the-mighty-midget","category-mccoy-lew","category-netherlands","category-tubes"],"_links":{"self":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/5726","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/comments?post=5726"}],"version-history":[{"count":0,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/5726\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/media?parent=5726"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/categories?post=5726"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/tags?post=5726"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}