Here is a nice trio pair of Miniwatt Dario 12AU7 ECC82 tubes. I can't pinpoint their exact origin and date of manufacture. If you have any ideas, please chime in.
Tube 1 has good green logo with 9.2 code. 12AU7 6150 *** is etched on glass. Tube has halo getter and 4 seams on top. This all suggests that it was made in a Philips factory in 1961. Tube 1 is sold.
Tube 2 has a good green logo with 10.7 code. 12AU7 58 9 is etched on glass. Tube has copper grid posts, no seams on top, and a D Getter. I am guessing September 1958 and either Siemens or Tungsram factory.
Tube 3 has very faded yellow logo with 12.5 code. No other information is visible. Construction is identical to tube 2.
Emissions results on my Sencore tester are 84/83, 85/87, and 87/88 on a scale where 70 is the minimum GOOD. Tubes were negative for shorts and grid leakage, and passed the life test. 12AU7 tubes consistently test about 10 points lower on the Sencore than other types.
Asking price is $35$25. Payment by PayPal with no fee. Add $2 for USPS 1st Class or $5 for USPS Priority Mail to USA.
