{"product_id":"tested-matched-pair-of-1955-western-electric-399b-tubes-date-codes-513-pentodes","title":"Tested Matched Pair of 1955 Western Electric 399B Tubes Date Codes 513 Pentodes","description":"\u003cdiv style=\"text-align: center;\"\u003e\u003cspan\u003e\u003cspan style=\"font-family: Arial;\"\u003eTested Matched Pair of 1955 Western Electric 399B Tubes.\u003c\/span\u003e\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv style=\"text-align: center;\"\u003e\u003cspan\u003e\u003cspan style=\"font-family: Arial;\"\u003e\u003cbr\u003e\u003c\/span\u003e\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv style=\"text-align: center;\"\u003e\u003cspan\u003e\u003cspan style=\"font-family: Arial;\"\u003eEach has a date code of 513 which places the production of both to January - March of 1955.\u003c\/span\u003e\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv style=\"text-align: center;\"\u003e\u003cspan\u003eTubes are closely matched for Gm testing (see below), date codes and internal structure - they are identical.\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv style=\"text-align: center;\"\u003e\u003cspan\u003e\u003cspan style=\"font-family: Arial;\"\u003e\u003cbr\u003e\u003c\/span\u003e\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv style=\"text-align: center;\"\u003e\n\u003cdiv\u003e\n\u003cspan style=\"font-family: Arial;\"\u003e\u003cspan\u003eTested on a calibrated Hickok TV-10 military tube tester\u003c\/span\u003e\u003cspan\u003e with \u003cb\u003eno shorts\u003c\/b\u003e and \u003cb\u003eno leaks\u003c\/b\u003e with the following results:\u003c\/span\u003e\u003c\/span\u003e\u003cspan\u003e\u003cspan style=\"font-family: Arial;\"\u003e\u003c\/span\u003e\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cdiv\u003e\n\u003cspan\u003e\u003cspan style=\"font-family: Arial;\"\u003e\u003cstrongr\u003e\u003c\/strongr\u003e\u003c\/span\u003e\u003c\/span\u003e\u003cbr\u003e\n\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan\u003e\u003cspan style=\"font-family: Arial;\"\u003eGm Test = 650 and 625 micromhos\u003c\/span\u003e\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan\u003e\u003cspan style=\"font-family: Arial;\"\u003eMinimum pass\/good = 440\u003c\/span\u003e\u003c\/span\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan\u003e\u003cspan style=\"font-family: Arial;\"\u003e\u003cbr\u003e\u003c\/span\u003e\u003c\/span\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"text-align: center;\"\u003e\u003cb\u003e~ Please view all 4 photos ~\u003c\/b\u003e\u003c\/div\u003e\n\u003cdiv style=\"text-align: center;\"\u003e\u003cb\u003e\u003c\/b\u003e\u003c\/div\u003e\n\u003cdiv style=\"text-align: center;\"\u003eGo\u003cb\u003e \u003ca href=\"https:\/\/classiccurrents.com\/collections\/western-electric-vacuum-tubes\" title=\"Western Electric Tubes\"\u003e\u003cstrong\u003eHERE\u003c\/strong\u003e\u003c\/a\u003e \u003c\/b\u003eto shop and explore all of our Western Electric tubes.\u003c\/div\u003e","brand":"Classic Currents","offers":[{"title":"Default Title","offer_id":47626451222783,"sku":null,"price":34.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0788\/5999\/3343\/files\/s-l1600-35_61651241-b2aa-400c-832f-56320e3ede17.webp?v=1764913898","url":"https:\/\/classiccurrents.com\/products\/tested-matched-pair-of-1955-western-electric-399b-tubes-date-codes-513-pentodes","provider":"Classic Currents","version":"1.0","type":"link"}