I was on eBay and saw some small green ferrite toroid cores, ten for 99 cents including shipping. I figured that since I had bought some larger green cores a few weeks ago and liked them, I couldn’t go wrong buying these since they were less than ten cents apiece.<\/p>\n
They were sent from an address in China.
\nFrom: 3 FLOOR 31 BUILDING, FUMING INDUSTRIAL PARK PINGFU TOWN LONGGANG DISTRICT SHENZEN
\nzip: 518111 tel: 13428933145<\/p>\n
This is the same address that the large cores were shipped from last month. Last month my email from PayPal showed the seller’s name in Chinese, which I can’t read.<\/p>\n
I received them this weekend and put one on my LC meter. I put a short piece of wire through the core and measured it, and like the larger cores, it measured about 1.3 uH. Then I wound about a foot of wire (about 18 turns) on it, and I measured 1.5 millihenrys. I wound another core with ten turns of 24 AWG solid insulated telephone wire and it measured 520 uH, which is a good value for a Joule Thief. There is still enough room to wind a second feedback winding on it. It would be okay to use 5 or 6 turns to give more than 100 uH, enough for a Joule Thief.<\/p>\n","protected":false},"excerpt":{"rendered":"
I was on eBay and saw some small green ferrite toroid cores, ten for 99 cents including shipping. I figured that since I had bought some larger green cores a few weeks ago and liked them, I couldn’t go wrong buying these since they were less than ten cents apiece. They were sent from an <\/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":[78,4,206],"tags":[],"class_list":["post-11179","post","type-post","status-publish","format-standard","hentry","category-inductors","category-joule-thief-smps-dc-dc","category-toroids-and-cores"],"_links":{"self":[{"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/11179","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=11179"}],"version-history":[{"count":2,"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/11179\/revisions"}],"predecessor-version":[{"id":11181,"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/11179\/revisions\/11181"}],"wp:attachment":[{"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=11179"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=11179"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=11179"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}