The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
The design and simulation of a predistortion type lineariser based on schottky diodes are proposed. With increase of input power, different combinations of the gain expansion and phase shift can be achieved over input power dynamic range. Because of this feature, it can compensate both AM-AM and AM-PM distortions for different travelling wave tube amplifiers (TWTAs) significantly. Also, it does not...
In filament-free magnetrons which are activated by electron emission from field-radiating cathodes its necessary level is provided by adsorption of active metal barium coming from the main palladium-barium cathode. The developed pressed palladiumbarium cathode allows to change barium evaporation speed due to change of its porosity and hence barium Knudsen flow. It will lead to emission level control...
We report on a new cathode which is based on die-pressed matrices made from scandia-doped tungsten powder. Transition temperatures from space charge to temperature limited emission are as low as 840° Cb(W) for emission of 5 Amps/cm2. Transitions are sharper than previously published scandate cathodes and compare favorably with M and ternary alloy cathodes. We present emission curves on several cathodes,...
Contact problems account for 40 percent of all electrical/electronic failures, ranging from small scale consumer electronic devices to large scale military and aerospace systems. This paper summarizes recent development on the theory of bulk contact and thin-film contacts, whose contact members may possess vastly different electrical resistivities. Current crowding at the rim of an electrode, scaling...
It was popular opinion that solid state was the future and vacuum tubes were an obsolete technology. After almost 20 years as a TWT engineer I subscribed to that ideal and left the industry only to return to the business 15 years later as an end user working with Satcom Amplifiers. So what does it takes to be a Vacuum Tube Engineer, how has the industry progressed and where does the future lie? Have...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.