Get On Board with. Compass Card. Compass Card is the smart card and smart choice for transit passes in the San Diego region. Compass Card is your ticket for the Bus, TROLLEY, COASTER, and SPRINTER.ompass Card. Compass Card is the smart card and smart choice for transit passes in the San Diego region. Compass Card is your ticket for the Bus, TROLLEY, COASTER, and SPRINTER.
Use of Vacuum Tube Diodes Gradually p-n junction semiconductor has come in the market and vacuum tubes got replaced by them. The most basic structure of vacuum tube is vacuum diode. Still today somewhere vacuum tubes are being used widely. These fields for application of the vacuum tubes are in Atomic Clocks; Audio Systems; Car Dashboards
Making the world better, one answer at a time. A vacuum breaker is a mechnical device used to avoid backflow or a negative pressure in a plumbing system. It typically consists of an air valve with a spring holding it closed. When the pressure within the system is positive, the valve remains closed. In a vacuum breaker the moving contact and fixed contact are sealed inside a vacuum chamber. Electrons cannot flow in a vacuum, therefore as soon as the moving contact s â¦ eperates from the fixed contact the arc meets an infinite resistance and is immediately extinguished.