The Power Supply to the Power Supply
The standard method of powering the unit is from a low voltage tapped AC source. The safest
available option is to use a ready made 'wallwart' or ‘line lump’ supply.
You can use any 15V or 18V AC output wallwart of linelump you can source. The current
capability of the mains adapter, sometimes incorrectly called the 'ampage', will determine the
maximum current draw of your PSU.
Maplin N57AT
This is a 500mA single phase AC output wallwart. It is a variable output type. This means it
has a little selector switch on the underside of the unit that allows you to change the output
voltage. You should select 15V for operation with the RPSU board. I do not recommend you
take more than 125mA per rail.
Because this is a single phase unit the Oakley PSU is wired in half-wave rectification mode.
You notice that only two wires come out of the wallwart and that you can select from a
variety of output socket types. Simply chose the one you would like to use on your system
and buy the appropriate socket for it to go into. I tend to recommend the 2.5mm DC power
plug one since this is the most common type of power socket.
You should fit fuse F2 only and it should be an anti-surge type and rated between 500mA and
1A.
Maplin N58AT
This is a 1A single phase unit. It has the potential to deliver up to 250mA per rail when the
Oakley PSU is used in half wave rectification mode.
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