It is important that you understand tube testing and what it means. Emission Tester's can tell you if the tube is shorted and will tell you if the filament is warming and emiting electrons. They can tell you if a tube has shorted or non function elements. They tell you if the tube is working and if the sections are functioning closely. They typically have a meter with bad/?/good divisions as well as numbers 0-100.  The biggest issues with them is that they will show different values depending on the plate voltage selected.  Unless you use a know good tube first, it is hard to tell if a tube is actaully comparable to a new tube. Most of these testers are quite old and the calibration is way off. They have the advantage of being very quick to use. Mutual Conductance Testers are much more complicated and if calibrated correctly, quite accurate. They put the tube under specific operating condtions and measure the current flow of the tube in those conditions. They will actually tell you how the tube compares to a new tube and how close the sections are in operation. They also tell you if the tube has shorts or leakage between the elements. Most however will not tell you if the tube is noisy or microphonic. This can only be determined accurately by listening to the tubes in an operating circuit.

Another note on tubes- I do not "clean" the tubes, so some have some dust or residue on them. If you use water or most cleaners you will remove the marking and lettering on tubes. If you remove the lettering it is impossible for me to identify that I sold you the tube and I will not accept ANY cleaned tubes for replacement! Please do not assume you will get the same readings with your tube tester, each brand and type will give different readings, especially if your tester has not been professionally calibrated.

This is the last pair of these that I have.  This auction is for a pair of 5814A/12AU7 dual triode tube. They are Sylvania BrandGreen label and JAN marked tubes. These are the ruggedizzed version of the 12AU7A tube and are also very low microphonic. The filament current draw is 25 MA higher than a standard 12AU7, but this isn't a problem. They are said to have been designed for the "new Tube computers". Extremely high quality tube

Tested on both an Emission tester and a Mercury 1000 Mutual Conductance tester, which has been recently rebuilt and calibrated by Roger Kennedy. 

Perfectly matched sections and pair

90/90   90/90

 Shipping is $9.00 via USPS  Priority  Mail  with DC in Continental US

I have been an electronic hobbyist for over 45 years. Most of my tubes come from test equipment that has been disassembled and parted out. I write articles, for AudioXpress concerning restoration, repair and maintenance of vintage audio equipment and radios.  I build custom audio amplifiers and speakers for customers, as well as for pleasure.  My interest is in preserving and promoting the use of many vintage items. I offer a restoration service for select audio brands including Heahtkit, Dynaco and McIntosh tube amplifiers.  I also collect and restore Bulova Accutron watches from the 60’s and 70’s and Zenith TransOceanic Radios from the 50’s and 60’s.   You can also check out the about me section by my screen name.

Terms and Shipping- Please read before you bid- Thanks

Terms- If you win an auction, you can pay at once, or wait for my invoice to be sent to you. If you anticipate buying multiple items please wait until I bill you at the end of my auctions. This way I can combine shipping where possible.  I accept PayPal payments ONLY. Once you are invoiced, please pay within 3 days.

I will ship as soon as I can after your payment. I use USPS Priority Mail with Delivery confirmation for small items, and Federal Express Home Delivery for larger items.

I want your item to reach you in great shape. I do NOT PROFIT from my shipping charges. Packing delicate items for survival is an art; it is time consuming and expensive. I charge only for the cost of the materials plus the actual shipping company costs. As examples, new boxes cost between $3-25 and a large roll of bubble wrap costs $54. Because all the major shipping companies will deny claims for items shipped in used boxes, I use new boxes for expensive and heavy equipment. I also double box any item that has tubes or glass, or is particularly fragile. This adds to the cost, but helps make sure your item arrives to you in the SAME CONDITION it was shipped. Proof of careful packing also facilitates any damage claims. (See below in FEEDBACK for general instructions on what to do if damage occurs during shipping.)

If you choose to ship by FED EX, and provided PayPal with a valid email address, you will receive tracking information from FED EX when your item ships, and communications regarding any issues they run into.

.You cannot directly email because of changes in eBay rules (they really want to control everything) if you have any questions you can go to the "me" at the top of the page and find my email there.