Matching networks up to 600W
Coaxial Power Systems Ltd manufacture range of styles of impedance matching
network to link the load to the RF generator. The purpose of the network is to
adjust the input impedance of the load to 50 Ohms so that maximum power is
transferred from the generator, whose output impedance is 50 Ohms, to the load.
Coaxial Power Systems Ltd. manufacture two types of network - Manual and
Automatic
Manual Matching Network
The manual matching network consists of two adjustable air vane capacitors
and a fixed inductor, which are usually arranged as an "L" network.
(The arrangement can be simply converted to a "Pi" network if
required). Geared drives with vernier dials are used to adjust the capacitors
for minimum reflected power as displayed on the generator reflected power meter.
When the reflected power is zero, the system is "tuned" and all of the
power output of the generator is being fed to the load.
Automatic Matching Network
The automatic matching network is similar to the manual version except that
servomotors drive the capacitors. At the input of the network, a phase and
magnitude detector determines the position of the capacitors. This information
is transferred to the separate controller. The controller then drives the
servomotors to the positions, which give zero, or minimum reflected power.
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