Up for your consideration are matched pair of Made in USA Amperex 7308/E188CC USN-CEP vacuum tubes with gold pins.
Painted letters are in very good shape and both tubes have identical construction.
These are made for US Navy, and they are exactly the same tubes as Amperex White Label PQ 7308 tubes.
(only with tighter and more stringent military spec)
They have "VR" code which indicates 7308 type tubes.
Etched Date Codes are VR5*4F and VR5*4A indicating they were made in June and January of 1964.
Also, printed letter of 64-47 and 64-22 indicates that they were packaged in 47th and 22nd week of 1964.
My most favorite 7308 tubes, Quiet, Dynamic, Tightly matched and Strong!
Many consider Amperex 7308 tubes the best of the best in 6DJ8 family tubes.
Rated to have 10,000 hours useful life!
Should last for years!
I have many more of these tubes, so please ask if you need more than one pair.
Shorts Test: Passed
Gas Test: Passed
Matching: As you can see in the Gm values, these are well matched. – within 8% for all 4 sections
Listening Test: Very good noise characteristics with no ringing
Gm Test: Both tubes test better than or very close to spec for new and closely matched with no issues.
Results are as follows:
Triode Section 1: 13500
Triode Section 2: 12700
Triode Section 1: 12300
Triode Section 2: 13300
Where minimum good is 7000
Value for new tube is 12500
I guarantee excellent performance, so bid with confidence.
If you are not satisfied with my tubes for any reason, I will issue full refund for your purchase price.
Buyer pays for return shipping (no returns so far).
Priority Mail shipping within US with delivery confirmation is $5.90.
USPS International First Class mail will be $10.
All tubes are tested by Hickok 539C vacuum tube tester. This tester was precision calibrated by Roger Kennedy to improve measurement accuracy. 83 and 5Y3 tubes were replaced by Solid State rectifiers to minimize calibration drift in the tester.
I also perform listening tests on them using Music Reference RM-4 pre-preamp (moving coil head amp), which has 30 db gain. This unit uses two 6DJ8 tubes (one for each channel). Each channel uses both sections of the 6DJ8 tube.