{"id":10358,"date":"2021-07-12T10:14:00","date_gmt":"2021-07-12T00:14:00","guid":{"rendered":"https:\/\/www.homebrewradio.us\/blog\/2021\/07\/12\/mythbuster-video-2-10-pole-crystal-filter\/"},"modified":"2025-07-22T18:04:40","modified_gmt":"2025-07-22T08:04:40","slug":"mythbuster-video-2-10-pole-crystal-filter","status":"publish","type":"post","link":"https:\/\/www.homebrewradio.us\/blog\/2021\/07\/12\/mythbuster-video-2-10-pole-crystal-filter\/","title":{"rendered":"Mythbuster Video #2  &#8212; 10 Pole Crystal Filter"},"content":{"rendered":"<p><iframe loading=\"lazy\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture\" allowfullscreen=\"\" frameborder=\"0\" height=\"247\" src=\"https:\/\/www.youtube.com\/embed\/XklWYurMauE?rel=0\" title=\"YouTube video player\" width=\"440\"><\/iframe><\/p>\n<div><\/div>\n<div><b><span face=\"Roboto, Arial, sans-serif\" style=\"background-color: #f9f9f9; color: #030303; font-size: 14px; letter-spacing: 0.2px; white-space: pre-wrap;\">This is a 5.2 MHz crystal filter. I used the G3UUR method for determining the crystal&#8217;s motional parameters. I then used Dishal and AADE software to design a 10 pole Cohn Min-Loss filter. I tested the bandwidth with an Antuino Scalar Network analyzer (thanks Farhan!) and a NanoVNA. I found the passband to be a bit tight for SSB, so I replaced the capacitors with caps of a slightly lower value &#8212; this broadened the passband. It is still a bit tight, but the SSB audio &#8212; while not enhanced or Hi-Fi &#8212; sounds fine. <\/span><\/b><b> <\/b><\/p>\n<p><b><\/b><\/p>\n<div class=\"separator\" style=\"clear: both; text-align: center;\"><b><a href=\"https:\/\/www.homebrewradio.us\/blog\/wp-content\/uploads\/2021\/06\/10polepassbandVNAandSNA.jpg\" style=\"margin-left: 1em; margin-right: 1em;\"><img loading=\"lazy\" decoding=\"async\" border=\"0\" data-original-height=\"1536\" data-original-width=\"2048\" height=\"300\" src=\"https:\/\/www.homebrewradio.us\/blog\/wp-content\/uploads\/2021\/06\/10polepassbandVNAandSNA.jpg\" width=\"400\" \/><\/a><\/b><\/div>\n<div class=\"separator\" style=\"clear: both; text-align: center;\"><b>Passband filter shape as seen in the Antuino and in the NanoVNA. The -20 db line in the Antuino actually corresponds to no loss. <\/b><\/div>\n<div class=\"separator\" style=\"clear: both; text-align: center;\"><b><br \/><\/b><\/div>\n<div class=\"separator\" style=\"clear: both; text-align: center;\"><b><br \/><\/b><\/div>\n<div class=\"separator\" style=\"clear: both; text-align: center;\"><b><a href=\"https:\/\/www.homebrewradio.us\/blog\/wp-content\/uploads\/2021\/07\/image252822529.png\" style=\"margin-left: 1em; margin-right: 1em;\"><img loading=\"lazy\" decoding=\"async\" border=\"0\" data-original-height=\"823\" data-original-width=\"911\" height=\"361\" src=\"https:\/\/www.homebrewradio.us\/blog\/wp-content\/uploads\/2021\/07\/image252822529.png\" width=\"400\" \/><\/a><\/b><\/div>\n<div class=\"separator\" style=\"clear: both; text-align: center;\"><b>The schematic provided by the AADE software. Dishal software may have come up with better, more correct values for the capacitors. <\/b><\/div>\n<div class=\"separator\" style=\"clear: both; text-align: center;\"><b><br \/><\/b><\/div>\n<div class=\"separator\" style=\"clear: both; text-align: center;\"><b><a href=\"https:\/\/www.homebrewradio.us\/blog\/wp-content\/uploads\/2021\/07\/3E11301393E24BAA84D1DE3EF6AB40F9.png\" style=\"margin-left: 1em; margin-right: 1em;\"><img loading=\"lazy\" decoding=\"async\" border=\"0\" data-original-height=\"334\" data-original-width=\"562\" height=\"238\" src=\"https:\/\/www.homebrewradio.us\/blog\/wp-content\/uploads\/2021\/07\/3E11301393E24BAA84D1DE3EF6AB40F9.png\" width=\"400\" \/><\/a><\/b><\/div>\n<div class=\"separator\" style=\"clear: both; text-align: center;\"><b>The passband as predicted by AADE. Skirts so nearly vertical as to strike fear in the hearts of SDR owners! <\/b><\/div>\n<div class=\"separator\" style=\"clear: both; text-align: center;\"><b><br \/><\/b><\/div>\n<div class=\"separator\" style=\"clear: both; text-align: center;\"><b><a href=\"https:\/\/www.homebrewradio.us\/blog\/wp-content\/uploads\/2021\/07\/6FC7823DADF440759984DEF2E3E295EE.jpg\" style=\"margin-left: 1em; margin-right: 1em;\"><img loading=\"lazy\" decoding=\"async\" border=\"0\" data-original-height=\"2048\" data-original-width=\"1536\" height=\"400\" src=\"https:\/\/www.homebrewradio.us\/blog\/wp-content\/uploads\/2021\/07\/6FC7823DADF440759984DEF2E3E295EE.jpg\" width=\"300\" \/><\/a><\/b><\/div>\n<div class=\"separator\" style=\"clear: both; text-align: center;\"><b>Filter under construction &#8212; waiting for the caps from Mouser. <\/b><\/div>\n<div class=\"separator\" style=\"clear: both; text-align: center;\"><b><br \/><\/b><\/div>\n<div class=\"separator\" style=\"clear: both; text-align: center;\">\n<div class=\"separator\" style=\"clear: both; text-align: center;\"><a href=\"https:\/\/www.homebrewradio.us\/blog\/wp-content\/uploads\/2021\/07\/IMG-2116.jpg\" style=\"margin-left: 1em; margin-right: 1em;\"><img loading=\"lazy\" decoding=\"async\" border=\"0\" data-original-height=\"1536\" data-original-width=\"2048\" height=\"300\" src=\"https:\/\/www.homebrewradio.us\/blog\/wp-content\/uploads\/2021\/07\/IMG-2116.jpg\" width=\"400\" \/><\/a><\/div>\n<\/div>\n<div class=\"separator\" style=\"clear: both; text-align: center;\"><b>First scan with the NanoVNA. Insertion loss looks very high but that is only because I am terminating the filter with resistors &#8212; I just wanted to see the passband shape. <\/b><\/div>\n<\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>This is a 5.2 MHz crystal filter. I used the G3UUR method for determining the crystal&#8217;s motional parameters. I then used Dishal and AADE software to design a 10 pole Cohn Min-Loss filter. I tested the bandwidth with an Antuino Scalar Network analyzer (thanks Farhan!) and a NanoVNA. I found the passband to be a &hellip; <a href=\"https:\/\/www.homebrewradio.us\/blog\/2021\/07\/12\/mythbuster-video-2-10-pole-crystal-filter\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Mythbuster Video #2  &#8212; 10 Pole Crystal Filter&#8221;<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":10359,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[109,16,132,191,23],"tags":[],"class_list":["post-10358","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-antuino","category-filters","category-mythbuster","category-nanovna","category-ssb"],"_links":{"self":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/10358","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\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/comments?post=10358"}],"version-history":[{"count":1,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/10358\/revisions"}],"predecessor-version":[{"id":10363,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/10358\/revisions\/10363"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/media\/10359"}],"wp:attachment":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/media?parent=10358"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/categories?post=10358"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/tags?post=10358"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}