Caledonian Audio Phono Classique, Assembly Manual

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Familiarize yourself with the schematics and the wiring diagram. Understanding
the circuit will help you to build this phono amplifier with confidence and
minimize risks of getting it wrong.
Study the wiring diagram and maybe try to visualize how your build before
actually doing it.
IMPORTANT NOTES ON HEATSINK AND VOLTAGE REGULATOR:
If you are to use the supplied heatsink (HS1) (for the 12VDC regulator chip), it
will be a good idea to attach the regulator chip (U1) onto the supplied heatsink
first before soldering the chip onto the PCB.
This enables you to correctly align the hole on the chip with the mounting hole
on the heatsink itself.
If you solder the chip onto the PCB first (without having it mounted on the
supplied heatsink), depending on the height of the legs inserted into the holes,
you might have some alignment issue later. So, please bear this in mind.
Once all preparations have been done, you can then start with stuffing and
soldering process.
2.1 Integrated Power Supply PCB
The integrated power supply PCB is responsible for converting AC voltages into
DC voltages for the phono amplifier board and the heater filaments for the three
valves.
The board is physically divided into two parts by an imaginary line in the middle
of the board. The top half is for managing the linear high voltage (B+) power
supply board and the bottom half is the regulated 12VDC. (The output is
actually 12.6VDC). See Figure 1 - Integrated power supply PCB.