air-core transformer

electronics

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Last updated

June 18, 2026

Quick Summary

An air-core transformer is a type of transformer that lacks magnetic material, such as iron, in its magnetic circuit. This design is specifically used for transferring radio-frequency currents, which are utilized in radio transmission.12

Transformers, in general, are electronic devices that transfer electrical energy between alternating-current circuits. They can either increase (step-up) or decrease (step-down) the voltage. This transfer of energy occurs through electromagnetic induction, where changes in current in a primary coil induce a current in a secondary coil. The voltage change is determined by the ratio of turns between the secondary and primary coils.2

Unlike iron-core transformers, which are used for audio frequencies, air-core transformers are optimized for higher radio frequencies.2

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transformer
Air-core transformers are designed to transfer radio-frequency currents—i.e., the currents used for radio transmission; they consist of two or more coils wound around a solid insulating substance or on an insulating coil form. Iron-core transformers serve analogous functions in the audio-frequency range.
Read More
Air-core transformers are designed to transfer radio-frequency currents—i.e., the currents used for radio transmission; they consist of two or more coils wound around a solid insulating substance or on an insulating coil form. Iron-core transformers serve analogous functions in the audio-frequency range.
Read More