Short Wave Diathermy (SWD) Frequency (ƒ) 10 7 – 10 8 Hz Radio wavelength (λ) 3 -30 m Commonly used frequency (ƒ) is 27.12 MHz and wavelength 11 m. It this current two circuits are used. Machine circuit is coupled with the patient circuit leading to resonance phenomenon, in this way patient is treated. A. Machine circuit: The basic oscillator circuit consists of condenser, inductance, and the currents of different frequencies are obtained by selecting suitable condenser and inductance. It a current of very high frequency is required, the condenser and inductance are very small. While to produce a current of lower frequency a larger condenser and inductance is used. B. Patient circuit: When SWD is applied by the condenser field method, the electrodes in the patient tissues form a capacitor, the capacitance of which depends upon the size electrodes and distance material between them. When the oscillator and resonator circuits are in t
Comments
Post a Comment