California Tube Laboratory, Inc. Electron tube and vacuum tube manufacturer. High power CW and pulse magnetrons, klystrons and power grid tubes. Product listings and data sheets, and outline drawings. http://www.caltubelab.com

Lohmann X-Ray Manufacturer of industrial and medical X-ray tubes, including tubes for medical, dental, and industrial applications. http://www.lohmannx-ray.com/

House of Tubes Ham radio and audio tubes. Online catalog with secure ordering. http://www.house-of-tubes.com/

Tube World, Inc. Vacuum tubes and sockets for sale. http://www.tubeworld.com/

Electron Tube Data Sheets Type index, high powered tubes and data sheets in PDF format. http://www.mif.pg.gda.pl/homepages/frank/

Electron Tubes for Industry Mostly industrial product line. http://www.elexs.com/2Xmtg.htm

Brand X-ray Tube Co., Inc. Manufacturer of x-ray tubes for use in medical, dental and industrial imaging and inspection applications. http://www.brandx-ray.com/

Antique Electronic Supply Books, transformers, capacitors, and resistors. Has an online catalog and shopping cart. http://www.tubesandmore.com/

The Invention of the Vacuum Tube In 1879, the American inventor Thomas Edison publicly exhibited his incandescent electric light bulb for the first time. http://www.maxmon.com/1883ad.htm

MachMat main Vacuum tubes for the audio amp market. http://www.machmat.com/sales/

Freeland Products, Inc. Rebuilder of vacuum power grid tubes for industrial, radio and television applications. http://www.freeland-inc.com/

The Tube Center Providing HAM and amateur radio operators, antique radio enthusiasts, audio professionals and hobbyists the ability to choose from an inventory over 2000 different tube types. http://www.thetubecenter.com/

20000 NOS Electron Tubes NOS and used tubes, rare valves, virtual museum. http://geocities.com/nikolic_lj_dragan/Tubes/NOSElectronTubes.htm

TubeTronic Vintage Vacuum Tubes and Test Equipment. Audio tubes, TV tubes, Radio tubes and Electron tubes. 12ax7, 12au7, 12at7, Generators, Analyzers, and Counters. http://www.TubeTronic.com

Kennetron, Inc Offering rebuilt vacuum, oscillator, induction and transmitter tubes. http://www.kennetron.com/

Mike's Electric Stuff Antique Glass and Vacuum stuff, for electronics and high voltage. http://www.netcomuk.co.uk/~wwl/electric.html

Yueqing Zhengli Rectifier Corp. Tube rectifiers. Site in English and Chinese. http://www.chinazenli.com/

Svetlana How a vacuum tube works. A good expalnation of how a tube works. http://www.svetlana.com/docs/tubeworks.html

Vacuum Tube Valley All about vacuum tubes. Tube audio amp kits. http://www.vacuumtube.com/

Tube Database Search From NJ7P Great site for tube searches. http://hereford.ampr.org/cgi-bin/tube