{"id":19095,"date":"2023-09-18T11:26:04","date_gmt":"2023-09-18T18:26:04","guid":{"rendered":"https:\/\/rustybolt.info\/wordpress\/?p=19095"},"modified":"2023-09-19T13:27:12","modified_gmt":"2023-09-19T20:27:12","slug":"2023-09-18-fm-transmitter-uses-square-loop-of-twisted-pair-wire","status":"publish","type":"post","link":"https:\/\/rustybolt.info\/wordpress\/?p=19095","title":{"rendered":"2023-09-18 FM Transmitter Uses Square Loop of Twisted Pair Wire"},"content":{"rendered":"\n

I’ve already shown the round loop FM microphone that I posted here – it used 12AWG solid bare copper house wire. I wanted to make a transmitter using loop out of thinner wire, which is more common. But thinner wire moves around too easily causing the frequency to change. So I twisted together three strands of 24 AWG solid copper insulated wire, I think that they’re from Cat 5 datacomm cable. They’re tightly twisted. Then to hold it still I taped the wires to the end of a 1.5 inch or 38mm square plastic tube a few inches long.<\/p>\n\n\n\n

The frequency is at the bottom of the FM broadcast band, around 90 MHz, but can be adjusted a few MHz with the ceramic trimmer capacitor labeled 2 in the photo. I put the 10 pF silver mica in parallel with the trimmer, but it would have been better to use a 6.8 pF (labeled 4) which would have allowed the trimmer to tune higher in the FM band.<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n
\"\"<\/figure>\n","protected":false},"excerpt":{"rendered":"

I’ve already shown the round loop FM microphone that I posted here – it used 12AWG solid bare copper house wire. I wanted to make a transmitter using loop out of thinner wire, which is more common. But thinner wire moves around too easily causing the frequency to change. So I twisted together three strands <\/p>\n

(Read More…)<\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-19095","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/19095","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=19095"}],"version-history":[{"count":1,"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/19095\/revisions"}],"predecessor-version":[{"id":19096,"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/19095\/revisions\/19096"}],"wp:attachment":[{"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=19095"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=19095"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=19095"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}