spark transmitter
Học thuậtThân thiện
Definition
Noun: - A historical type of radio transmitter: A "spark transmitter" is an early, now obsolete, device for generating radio waves. It operates by creating a high-voltage electric spark across a gap between two electrodes. This spark produces a broad, noisy signal used for wireless telegraphy, primarily for Morse code communication.
Examples of Usage
- Noun:
- The Titanic was equipped with a powerful spark transmitter to send distress signals.
- Early radio pioneers like Marconi relied on spark transmitters for their first transatlantic experiments.
- The signal from a spark transmitter sounds like a raspy buzz, unlike the pure tones of modern transmitters.
Advanced Usage
- Technical Operation: The core component is the spark gap. A capacitor is charged to a high voltage until it discharges across the gap, creating a spark. This abrupt discharge excites oscillations in an attached antenna circuit, radiating a damped wave signal.
- Historical Context: Spark transmitters were the first practical means of radio communication but were inefficient and produced wideband interference that could disrupt multiple frequencies. Their use was largely phased out by the 1920s in favor of continuous wave transmitters.
Variants and Related Words
- Spark Gap (n): The physical space between two electrodes where the electrical discharge (spark) occurs. It is the key component of a spark transmitter.
- Damped Wave (n): The type of radio wave produced by a spark transmitter, characterized by a rapidly decreasing amplitude, which creates its distinctive broad, noisy signal.
- Continuous Wave (CW) Transmitter (n): The later technology that replaced spark transmitters, producing a clean, single-frequency signal essential for voice transmission and more efficient telegraphy.
Synonyms
- Spark-gap transmitter: A full, technical synonym.
- Damped wave transmitter: A synonym describing the type of wave it produces.
Related Phrases
- Spark telegraphy: The method of wireless communication using spark transmitters to send Morse code.
- Spark coil: A type of induction coil often used to generate the high voltage needed for the spark gap in smaller transmitters.
Noun
- an early radio transmitter using a discharge across a spark gap as the source of its power