{"product_id":"high-impedance-headphone-earphone-brunet-paris-type-f-2000-ohms-dc-6k-reactive","title":"High Impedance Headphone Earphone Brunet Paris Type F 2000 Ohms DC 6K Reactive","description":"This is one item of original high impedance earphone made by Brunet \u0026amp; Company, Paris at some point in the first half of the 20th century. The measured D.C. resistance is a little over 2K Ohms. You can use these for crystal sets, vintage radios, and they work fine when plugged directly into the headphone socket on my Murphy B40 valve communications receiver. I've tested these on a crystal set too.\u003cbr\u003e\u003cbr\u003eThe D.C. resistance across the connections measures over 2000 Ohms, though if you bother to measure the reactive impedance at 1kHz, it's more like 6K Ohms in total due to the inductance of the internal windings as seen in the video clip and pictures.\u003cbr\u003e\u003cbr\u003eExamples of crystal set radios can be seen here:\u003cbr\u003e\u003cbr\u003eCrystal Set One\u003cbr\u003ehttps:\/\/www.interestingelectronics.com\/old\/henrys_interesting_electronics\/loud_crystal_set_radio\/loud_crystal_set_radio.htm\u003cbr\u003e\u003cbr\u003eCrystal Set Two\u003cbr\u003ehttps:\/\/www.interestingelectronics.com\/old\/henrys_interesting_electronics\/crystal_radio_v2\/crystal_set_radio_v2.htm\u003cbr\u003e\u003cbr\u003eChoccy Block Crystal Set Radio Kit\u003cbr\u003ehttps:\/\/www.usefulcomponents.com\/main_contents\/projects\/choccy_block_crystal_radio\/choccy_block_crystal_radio.html","brand":"Brunet","offers":[{"title":"Default Title","offer_id":58501260050816,"sku":null,"price":9.9,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1007\/2136\/1280\/files\/il_fullxfull.6127721352_sqgj.webp?v=1785182346","url":"https:\/\/shop.usefulcomponents.com\/products\/high-impedance-headphone-earphone-brunet-paris-type-f-2000-ohms-dc-6k-reactive","provider":"HJW Electronics","version":"1.0","type":"link"}