{"product_id":"6sn7gta-rca-radiotron-matched-pair-silver-logo-black-plates-d-side-getter-amplitrex-tested","title":"6SN7GTA RCA Radiotron Matched Pair Silver Logo Black Plates D Side Getter AMPLITREX Tested","description":"\u003ch3 class=\"p1\"\u003e\u003cstrong\u003e6SN7GTA RCA Radiotron Matched Pair Silver Logo Black Plates D Side Getter -  Made In USA - 1950s\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp class=\"p1\"\u003e\u003cb\u003eAMPLITREX Tested – VERY STRONG \u003cmeta charset=\"utf-8\"\u003e– Vintage American RCA Production\u003c\/b\u003e\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eTest Results:\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eTubes tested on \u003cstrong\u003eAmplitrex AT-1000 Tube tester\u003c\/strong\u003e:\u003c\/p\u003e\n\u003cul\u003e\n\n\u003cli\u003e\n\n\u003cstrong\u003eTest Conditions:\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eVa = 250V, Vg = -8V\u003c\/li\u003e\n\n\u003cli\u003e\u003cstrong\u003eAverage 100% Gm = 2600 ; Ia = 9.0 mA\u003c\/strong\u003e\u003c\/li\u003e\n\n\u003cli\u003e\n\n\u003cstrong\u003eTest Result:\u003c\/strong\u003e VERY STRONG\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\u003cp class=\"p1\"\u003e\u003cb\u003eTube #1\u003c\/b\u003e\u003c\/p\u003e\n\u003cul\u003e\n\n\u003cli\u003e\n\n\u003cstrong\u003eSection 1: \u003c\/strong\u003eGm = 2400 ; Ia = 7.6 mA\u003c\/li\u003e\n\n\u003cli\u003e\n\n\u003cstrong\u003eSection 2: \u003c\/strong\u003eGm = 2400 ; Ia = 8.3 mA\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\u003cp class=\"p1\"\u003e\u003cb\u003eTube #2\u003c\/b\u003e\u003c\/p\u003e\n\u003cul\u003e\n\n\u003cli\u003e\n\n\u003cstrong\u003eSection 1: \u003c\/strong\u003eGm = 2300 ; Ia = 7.0 mA\u003c\/li\u003e\n\n\u003cli\u003e\n\n\u003cstrong\u003eSection 2: \u003c\/strong\u003eGm = 2300 ; Ia = 7.4 mA\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\u003ch3 class=\"p1\"\u003e\u003cb\u003eDescription\u003c\/b\u003e\u003c\/h3\u003e\n\u003cp data-pm-slice=\"1 1 []\"\u003e\u003cspan\u003eSelected vintage pair of \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e6SN7GTA RCA Radiotron\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, produced in the United States in \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e1954\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e and carefully matched as a \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eMatched Pair\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e. Both specimens feature the characteristic \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eBlack Plates with D Side Getter\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e construction, a configuration representative of the historic American RCA production of the 1950s. The manufacturing markings identify two different periods of the same year, the 22nd and 52nd weeks of 1954, respectively, while the internal construction retains common characteristics. The classic \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eSilver Logo RCA Radiotron\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, partially preserved, testifies to the authenticity of these vintage tubes.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe measurements performed with the \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eAmplitrex AT-1000\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e highlight a consistent electrical match. The transconductance of the four sections is between \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e2300 and 2400 µmhos\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, with averages of \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e2400 and 2300 µmhos\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, respectively, compared to the nominal reference of 2600. The anode currents range from 7.0 to 8.3 mA, with averages of \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e7.95 and 7.2 mA\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e. Particularly significant is the \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003etransconductance balance\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, identical between the two sections of each tube, a favorable characteristic in applications requiring a good internal balance.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eBoth tubes have been subjected to instrumental tests that confirmed \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003every strong and stable emission\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, without fluctuations, short circuits, or presence of gas. The noise and microphony levels fall within the \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eStandard\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e classification, making them suitable for use in hi-fi equipment and musical amplifiers, preferably in the less sensitive stages.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e6SN7GTA RCA Black Plates\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e find application in hi-fi preamplifiers, headphone amplifiers, driver stages, and compatible phase inverter circuits. RCA production from this period is traditionally appreciated by audiophiles for a musical presentation generally described as \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003efull-bodied, balanced, and natural\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, with a midrange rich in nuances and a pleasant expressive fluidity.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe value of this pair lies in the \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eauthenticity of the 1954 RCA production\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, the common \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eBlack Plates with D Side Getter\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e construction, and the documented electrical characteristics. The partially eroded screen printing and signs of use tell their story, without compromising their verified functionality. Two authentic \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003evintage RCA Radiotrons\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e, carefully tested and matched, intended for enthusiasts who wish to rediscover the character of historic American tubes through original and selected specimens.\u003c\/span\u003e\u003c\/p\u003e\n\u003chr\u003e\n\u003ch3 class=\"p1\"\u003e\u003cb\u003eAdditional tests:\u003c\/b\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\n\u003cli class=\"p1\"\u003e\n\n\u003cspan class=\"s1\"\u003e\u003cb\u003eMicrophony and noise:\u003c\/b\u003e\u003c\/span\u003e Standard. Tested and suitable for use in hi-fi equipment and guitar amplifiers. Recommended in V2, V3, and V4 positions, as drivers or in the less critical stages. For V1 and for the highest gain positions particularly sensitive to microphony, we recommend a tube with a low microphony selection.\u003c\/li\u003e\n\n\u003cli class=\"p1\"\u003e\n\n\u003cspan class=\"s1\"\u003e\u003cb\u003eBalance:\u003c\/b\u003e\u003c\/span\u003e Very good. The sections are consistent and well aligned, making the tube suitable even for use as a phase inverter in hi-fi and instrumental applications.\u003c\/li\u003e\n\n\u003cli class=\"p1\"\u003e\n\n\u003cspan class=\"s1\"\u003e\u003cb\u003eEmission:\u003c\/b\u003e\u003c\/span\u003e Excellent – Very strong and stable emission, without fluctuations.\u003c\/li\u003e\n\n\u003cli class=\"p1\"\u003e\n\n\u003cb\u003eShort circuits \/ Gas:\u003c\/b\u003e\u003cspan class=\"s1\"\u003e absent\u003c\/span\u003e\n\n\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\u003ch3 class=\"p1\"\u003e\u003cstrong\u003eCondition\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\n\u003cli class=\"p1\"\u003e\n\n\u003cspan class=\"s1\"\u003e\u003cb\u003eCondition:\u003c\/b\u003e\u003c\/span\u003e Vintage Tubes - Tested and perfectly functional. Supplied in our custom box for optimal protection.\u003c\/li\u003e\n\n\u003cli class=\"p1\"\u003e\n\n\u003cspan class=\"s1\"\u003e\u003cb\u003eFunctionality:\u003c\/b\u003e\u003c\/span\u003e Perfectly operational\u003c\/li\u003e\n\n\u003cli class=\"p1\"\u003e\n\n\u003cspan class=\"s1\"\u003e\u003cb\u003eAesthetic condition:\u003c\/b\u003e\u003c\/span\u003e One tube in sufficient condition, with the screen printing almost completely absent and evident signs of use, the other in Good condition – Markings partially eroded, but still legible. Tube body in good condition. See photos for details.\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eManufacturing codes:\u003c\/strong\u003e \u003c\/p\u003e\n\u003cul\u003e\n\n\u003cli\u003e4-22 274 → RMA\/EIA Open Date Code → manufactured in the 22nd week of 1954 - 274 → Radio Corporation of America, Camden, N. J.\u003c\/li\u003e\n\n\u003cli\u003e\n\n\u003cmeta charset=\"utf-8\"\u003e4-52 → RMA\/EIA Open Date Code → manufactured in the 52nd week of 1954 - by Radio Corporation of America, Camden, N. J.\u003c\/li\u003e\n\n\n\u003c\/ul\u003e\n\u003cp\u003e\u003cmeta charset=\"utf-8\"\u003e\u003ca href=\"https:\/\/vacuumtubestreasures.com\/blogs\/notizie\/perche-le-nostre-valvole-sono-diverse\" title=\"Why our tubes are different – the VTT protocol that improves sound, reliability, and longevity\" rel=\"noopener\" target=\"_blank\"\u003e\u003cstrong\u003eDiscover why our tubes are different →\u003c\/strong\u003e\u003c\/a\u003e\u003c\/p\u003e","brand":"RCA","offers":[{"title":"Default Title","offer_id":59738330857820,"sku":"03910","price":359.0,"currency_code":"ILS","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0616\/3775\/5127\/files\/2_ff15f9c1-2a02-49a9-b667-b9ef8fa81be0.jpg?v=1793640989","url":"https:\/\/vacuumtubestreasures.com\/en-il\/products\/6sn7gta-rca-radiotron-matched-pair-silver-logo-black-plates-d-side-getter-amplitrex-tested","provider":"Vacuum Tubes Treasures","version":"1.0","type":"link"}