{"id":10189,"date":"2014-12-04T06:32:30","date_gmt":"2014-12-04T14:32:30","guid":{"rendered":"http:\/\/rustybolt.info\/wordpress\/?p=10189"},"modified":"2014-12-04T09:05:54","modified_gmt":"2014-12-04T17:05:54","slug":"2014-12-04-rf-interference-from-dc-dc-converter","status":"publish","type":"post","link":"https:\/\/rustybolt.info\/wordpress\/?p=10189","title":{"rendered":"2014-12-04 RF Interference From DC-DC Converter"},"content":{"rendered":"<p>I&#8217;ve been using these DC-DC converters for charging cell phones in my car and in the house (more in <a href=\"http:\/\/rustybolt.info\/wordpress\/?p=9946\">this blog<\/a>) and they work fine.&nbsp; But when I plug my phone in, my FM radio station gets a lot of RF interference.&nbsp; I admit that the station, KSBR, which is low power and far away, has a weak signal, and that makes the problem worse.&nbsp; If the station was a powerful commercial station, the problem would probably be less, or not a problem if I moved the charger a few feet away from the radio.<\/p>\n<p>But I like playing, er, experimenting with ferrite toroids and the like, so I decided to try putting RF interference suppressors on the cables.&nbsp; Most of us have seen the big plastic cylindrical thing on cables next to the connectors.&nbsp; This is a cylinder of ferrite.&nbsp; It&#8217;s like putting 4 or 5 toroids next to each other on the cable.&nbsp; These are effective at choking off and absorbing the RF interference coming out of the equipment by way of the cable.<\/p>\n<p>I found some reasonably priced <a href=\"http:\/\/www.allelectronics.com\/make-a-store\/category\/235\/ferrites\/1.html\">snap-on RFI suppressors<\/a> at All Electronics.  At $0.75 each, I can get a dozen for about ten dollars US and snap them on to both ends of the cables.  I have already put the small ends of cables through a larger toroid, and it helped some.  But I still hear some interference when it&#8217;s charging.  So I ordered one size for larger cables and one for smaller cables.  I guess they will arrive early next week.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>I&#8217;ve been using these DC-DC converters for charging cell phones in my car and in the house (more in this blog) and they work fine.&nbsp; But when I plug my phone in, my FM radio station gets a lot of RF interference.&nbsp; I admit that the station, KSBR, which is low power and far away,<a href=\"https:\/\/rustybolt.info\/wordpress\/?p=10189\"> <\/p>\n<p> (Read More&#8230;)<\/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-10189","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/10189","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=10189"}],"version-history":[{"count":3,"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/10189\/revisions"}],"predecessor-version":[{"id":10193,"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/10189\/revisions\/10193"}],"wp:attachment":[{"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=10189"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=10189"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=10189"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}