A VALVE CURE

Radio Record, Volume I, Issue 26, 13 January 1928, Page 16

A VALVE CURE

--eeewewees | FILAMENY TOUCHES GRID, It sometimes happens that the grid. of a valve touches the filament or, if the valve is :nounted horizontally, thie filament may sag on the grid. When this occurs some temedy is necessary, for the set will not operate with the valves in that condition. If the grid has not stuck to the filament at can be jatred away by rapping the tube on the palm of the hand. At tunes, however, this is not sufficient. If you are not sure whether the grid and filament are touching, or some‘thing else may be wrong, you can find out easily by connecting two volts from one ccll of your storage battery across one of the filament contact pins and the grid contact pin If one-half the filament lights, you may know that they are touching. Do not apply the full voltage, for that might burn out ‘the filament with only one-half of it offering resistance in the circuit. | If the grid and filament are stuck |together connect both filament terminals ‘together aid put two volts across the | grid and filament contections. Then, while the filament is dimly lighted strike the tube on the palm of your hand gently. This will cause the grid to become disengaged, Then it can be jarred back into its place,