Impedance matching: Difference between revisions
Jump to navigation
Jump to search
(New page: Impedance Matching is required to '''maximise energy transfer''' from an AC source to a device. <u>Examples</u>: * Transform 240V AC to 12V AC for a power supply. * Transform a 7 Kohm au...) |
(No difference)
|
Revision as of 19:34, 3 April 2009
Impedance Matching is required to maximise energy transfer from an AC source to a device.
Examples:
- Transform 240V AC to 12V AC for a power supply.
- Transform a 7 Kohm audio source (from an amplifier for instance) down to 16 Ohms for a headphone or loudspeaker.
- both of these can be done by using a transformer.
- Couple an antenna with impedance other than 50 Ohm and non-zero reactance to a transceiver with 50 Ohm purely reactive impedance.
This is done by an ATU. The simplest form of an ATU consists of a variable capacitor between TRTX and ground followed by a series variable inductor, which in turn is followed by a series variable capacitor which leads to the antenna (in case of an unbalanced feed line).