G.E ONE (1) 5U4GA tNOS AT1000 TESTED Vacuum Tube balanced Audio 1954-1960

This listing is for one (1) GE-made 5U4GA vacuum tube in the straight-walled glass tube shape. It has a black bakelite octal base, black plate, and side or top D getter. Some were made for OEM Hallicrafters, Magnavox, Zenith, Westinghouse.

The ones made in 1954-1956 are labeled as 5U4GA on the glass and the base. In 1957, the same tubes were labeled as 5U4GA/GB on the base, but etched 5U4GA on the glass. These tubes are distinct from the 5U4GB that GE made later (and all other 5U4GBs!) by having glass that is almost exactly the same diameter as the base. All 5U4GBs (except those described immediately following) have glass that is a few mm wider in diameter than the base. From the 13th week of 1958 through the 13th week of 1959, GE made 5U4GB tubes in the narrow bottle as well, but those are not included in this listing.

Your tube has been fully tested on a computer-regulated, USA-made Amplitrex AT1000 with balanced elements and like new, NOS results (tNOS). Here's what that means: to qualify for this listing, several stringent conditions must be met: The forward voltage drop (associated with sag) in the two sections must be balanced within 10% of each other, and that voltage must be between 21 and 28 Volts for both sections, consistent with original 1954 RCA, Western Electric, Sylvania, GE, and/or Tung-Sol datasheet specifications for new tubes of this type. The tube must also show no shorts. The tube might have mechanical wear or have the label rubbed off - these are very old! Unbalanced and used-testing tubes are available in a separate listing at a significant discount. Every tube you receive from Sound By Doc is guaranteed against failure for 60 days after purchase, an industry extreme!

OPTIONS (use offer feature in Reverb):

Want a regular white box? $1 extra per tube
Want a tube that's packed in its original box? $3 extra per tube
Want the test results recorded on your box, too? $3 extra per tube
Want two tubes that match one another within 10% for voltage drop? $5 extra per tube.
Comfortable using a replaced guide pin? Save $1 (and get the replacement guide pin included, installed!)