2 x 12ax7 Siemans Tubes Made in Germany for Sonotone Ribbed plates Tested on Enhanced Triplett E3444 Laboratory Tester prepared by Paul hart Results= 1600/1700 micromhos @ 1.11 & 1.21 mA 1500/1630 micromhos @ .83 & .99 mA Bogey(100% or New) = 1600/1600 micromhos @ 1.2/1.2 mA +/- 10% The measurements in this listing were taken on a Triplett 3444 modified to test the tube as an amplifier in accordance with RMA/EIA specifications, utilized by all US and most foreign tube manufacturers. This tester applies test conditions for this tube as shown below (including the precise filament voltage) and then measures transconductance (gm) in accordance with the engineering definition of gm. Tubes may also be operated under the test conditions for extended periods to be sure that it is stable. A tube must be tested in this manner to compare its test results with the manufacturer’s original intent or with other tubes of the same type. Most tube testers do not apply the test conditions required or conduct a valid gm test. For more details on the test and our test equipment, please contact us.The test conditions for this listing are__250_Volts plate, __250_Volts screen, ___-2.0___Volts bias or Cathode resistance*What were your tubes tested at? I do combine S&H

2 x 12ax7 Siemans Tubes Made in Germany for Sonotone Ribbed plates Tested on Enhanced Triplett E3444 Laboratory Tester prepared by Paul hart Results= 1600/1700 micromhos @ 1.11 & 1.21 mA 1500/1630 micromhos @ .83 & .99 mA Bogey(100% or New) = 1600/1600 micromhos @ 1.2/1.2 mA +/- 10% The measurements in this listing were taken on a Triplett 3444 modified to test the tube as an amplifier in accordance with RMA/EIA specifications, utilized by all US and most foreign tube manufacturers. This tester applies test conditions for this tube as shown below (including the precise filament voltage) and then measures transconductance (gm) in accordance with the engineering definition of gm. Tubes may also be operated under the test conditions for extended periods to be sure that it is stable. A tube must be tested in this manner to compare its test results with the manufacturer’s original intent or with other tubes of the same type. Most tube testers do not apply the test conditions required or conduct a valid gm test. For more details on the test and our test equipment, please contact us.The test conditions for this listing are__250_Volts plate, __250_Volts screen, ___-2.0___Volts bias or Cathode resistance*What were your tubes tested at? I do combine S&H

I have 1 Excellent strong super nice siemens Germany made dimple top EL34 tube.This tube test 47 where 30 is the minimum good and new tubes test 48 to 50 on are tv7 tube tester.

SIEMENS PLATES BALANCED ECC83 12AX7 VINTAGE TUBE VALVE SUPER RARE COLLECTIBLE, AND DECORATIVE Well protected and tracking number. $ $ $ $ ! ! ! GREAT PRICES ! ! ! $ $ $ $ For any problem our question about the item please message me i will be glad to help.For Shipping Charges for other countries, please, contact the seller. Bidders from outside the European Union are welcome.Appreciate feedback soon as you get the item. PLEASE contact me before complaining to Ebay, I am POSITIVE that we can work something out that both of us will be happy with. CHECK OUT MY OTHER ANTIQUES COLLECTIBLES ITEMS !!! THANKS FOR LOOKING AND GOOD BIDDING