Introduction
This is the User Manual for issue 2 of the PSU circuit board from Oakley Sound. The Oakley
PSU is a power supply unit designed to be used in conjunction with the Oakley Dizzy power
distribution system.
When built onto the 3U master panel the maximum peak current output is 520mA per rail
using the recommended Yamaha PA-20 power supply. When built onto the larger 4U 19” rack
panel and using the Yamaha PA-30 power supply the maximum current draw is 780mA per
rail.
It is possible to upgrade the power supply's maximum current capability using a different
power source and suitable smoothing capacitors and appropriate heatsinking.
As well as giving details as to what the PSU board does, this document contains instructions
on how to wire up your board to your source of power, any external switches and the optional
power indicators. We will also look at the Oakley power buss and how it differs from the
MOTM one yet retains complete compatibility with it. I will also give you some information
about suitable sources for your low voltage AC power supply.
The Oakley PSU allows for various options in the installation. You can use the unit either in
full wave rectification mode for connection to tapped linelumps or twin transformer
secondaries, or in half wave rectification for single phase AC output wallwarts and linelumps.
If all this sounds very confusing at the moment, do not worry, in this manual I will try to make
it clearer so that you make the right decision about what power source you will need.
If you are building the PSU as a complete DIY project please also download the latest
Builder's Guide. This can be found on the main PSU webpage along with our very useful
generic parts and construction guides.
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