control grid
Học thuậtThân thiện
Definition
Noun: 1. An electrode placed between the cathode and anode of a vacuum tube to control the flow of electrons through the tube: A control grid is a key component in electronic devices like vacuum tubes (thermionic valves). It is a mesh or spiral of wire positioned between the electron-emitting cathode and the electron-collecting anode. By applying a small voltage to this grid, it can regulate (control) the much larger current of electrons flowing from the cathode to the anode, enabling amplification and switching functions.
Usage Examples
- In early radios and amplifiers, the control grid was essential for signal amplification.
- The technician adjusted the voltage on the control grid to modify the tube's output.
- A vacuum tube typically contains a cathode, an anode, and one or more grids, with the control grid being the primary one for signal input.
Advanced Usage
- Grid Bias: The steady DC voltage applied to the control grid to set its operating point. "The amplifier's distortion was caused by an incorrect grid bias."
- Grid Leak Resistor: A resistor connected to the control grid to provide a path for accumulated charge to leak away.
Variants and Related Words
- Grid (noun): Often used as a shortened, informal form of "control grid" in electronics contexts.
- Screen Grid (noun): A second grid in a vacuum tube (like a tetrode) placed between the control grid and the anode to shield the control grid from the anode's electric field.
- Suppressor Grid (noun): A third grid in a vacuum tube (like a pentode) placed to suppress secondary emission of electrons from the anode.
Synonyms
- Grid Electrode: A more general technical term.
- Control Electrode: A functional description of its role.
Related Phrases
- Grid Voltage: The electrical potential applied to the control grid.
- Grid Current: The small current that flows into or out of the control grid circuit.
Noun
- an electrode placed between the cathode and anode of a vacuum tube to control the flow of electrons through the tube