Sylvania JAN 5U4GB tNOS AT1000 TESTED Vacuum Tube balanced military rectifier 1966-1979

This listing is for one (1) Sylvania-made JAN 5U4GB rectifier vacuum tube in the straight-walled glass tube shape. It has a black bakelite octal base, black plate, and top halo getter.

We have JAN-5U4GB, JAN-CHS-5U4GB, and USN-CHS-5U4GB in stock. Please ask if you don't see what you'd like.

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 1966 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 tNOS or Used Good tube you receive from Sound By Doc is guaranteed against failure for 60 days after purchase, an industry extreme!

These photos are not stock photos. You are looking at the actual tube you will receive. If a box or boxes are in the photos, you will get them. If test results appear in the photos, look close, because those are the test results of the tube you will receive! SKU 5U4-GBm312. Please note that matching is nearly always possible for us from stock that is inventoried but not yet listed. If you need a matched pair or quad etc., please use the make-an-offer feature through Reverb. Matching requires an extra burst of effort, so please add $5 per tube to your offer for 10% matching and $10 per tube for 4% matching. [Matching is based on plate current for power tubes, voltage drop for rectifiers, and GM for all other tubes. If you also require the label or internals to match, please specify that in your offer.]