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Section 2: Building the Power Supply PCB
This section details the process of building the power supply circuit board. We start with
an overview on this page. The specifics you need to start building begin on the next page.
The bare power supply PCB is shown in Figure 1.
Figure 1-Component side of power supply PCB before loading
Begin by carefully emptying the contents of the envelope marked “GT-102 PSU Module”
into a broad soup bowl, as shown below. In general, you’ll start with the components that
lay closest to the board, working your way towards the taller components. You will:
1.
Install the resistors (all but one
power resistor, left for later)
2.
Install the diodes
3.
Install the capacitors
4.
Install the integrated circuits.
5.
Install the transistors
6.
Install the pass transistor Q5 as you
mount the PCB to the heat sink.
Component Order
You’ll notice that the component designations in the directions don’t go exactly in order.
We have grouped them so that all components with the same value appear together. This
makes assembly easier. You’ll find in the parts kit that similar parts, e.g. 3 1K resistors,
are typically (though not always) taped together.
Install the Resistors
In general, you install the resistors by placing the body on the silk screen side of the
board, and the leads through the indicated holes. Bend the leads over on the back of the
board to keep the resistors from falling out until your solder them in place. Try to bend
the leads in a direction that won’t lead to solder bridges between traces that should
remain disconnected.