At the meeting of the Lothians Radio Society on 22nd February LRS member Dr. Brian Flynn GM8BJF described how to modify computer power supply units for use in Amateur Radio. The talk started off with a description of the operation of SMPS – Switch-Mode Power Supplies – and an explanation of the commonly used topologies (circuit configurations). Finally he advised on how to choose “good” ones for conversion. Full Powerpoint presentation is on Brian’s Website. (No longer available – psp).
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Brian GM8BJF demonstrates a typical PC PSU suitable for modification for use in Amateur Radio.
These PSUs come with a number of connectors supplying different voltages including 5V and 12V.
Typical radio use would employ the 12V supply, modified to provide 13.6V.
A selection of PC PSUs from Brian’s garage!
Demonstration of voltage stabilization by providing a fixed load on the 5V supply.
Note essential liquid fuel supply.
The rapt audience of LRS members following Brian’s demonstration.