Long plate, square getter, Factory code mC1 B5J, which I think confirms it was manufactured at the Blackburn factory in October 1955. Tested on an AVO CT160 before being put into storage some years ago. The two sections tested at 1.5 and 1.3 mA/V respectively, so a good strong result. Incidentally, the test results written on the valve are in black felt pen and will simply wipe off with alcohol.
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Date Code: f92 B8L, f92 B8K. 2x Mullard ECC83 Valves. This valve has also been tested in amplifier without any noise. Ia1 = 1.15(mA), gm1 = 1.4(mA/V). NOS specification: Ia = 1.2(mA), gm = 1.6(mA/V).
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ULTRA-RARE MULLARDMILITARY GRADE M8137 CV4004 ECC83 12AX7. Date code indicates it was manufactured in the UK in April 1958. Tested on an AVO Mk III VCM.
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2x Mullard ECC83 Valves. This valve has also been tested in amplifier without any noise. NOS specification: Ia = 1.2(mA), gm = 1.6(mA/V). Ia2 = 1.3(mA), gm2 = 1.6(mA/V). Ia1 = 1.6(mA), gm1 = 1.7(mA/V).
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Four working ECC83 valves. Three Mullards and one Brimar, all with Halo Getters. These have been tested as good on a CT160 with the following results Brimar 2D2/1674. Mullard B5C3. 2 Mullard B4C3.
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ECC83 12AX7 Valve Tube. Mullard Blackburn, Made in Great Britain. Short Grey Plates, Halo Getter. Fully Tested on AVO VCM 163.
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Mullard ECC83 (12AX7) I65 ◢1k3 Double Triode Med Plate Halo Tests Good Holland See photos for condition. Tests good on Taylor Model 45C valve tester. Triode 1 mutual conductance reading Gm 2.2 Triode 2 mutual conductance reading Gm 2.5 100% factory data in Taylor manual at Gm 2.0 UK shipping with MyHermes Tracked or Royal Mail. International shipping with Royal Mail International Tracked. I will combine postage on multiple valve orders. See my other listings!
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Here we have for sale is an incredibly rare ANOS tested Mullard 10m 12AX7 ECC83 Gold Pin Tube. Probably the most sought after Holy grail 12AX7 ECC83 tube that people are after for their collection. Factory tested and Selected tube chosen to be one of the highest quality 12AX7 ECC83 tubes Mullard was capable of producing.
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