Figure 3 shows the PCB after the layout has been sketched on the tinned copper surface using a red felt tip pen. There is no attempt to produce intricate artwork, just the simple functional areas that are required to make the connections. At a later stage two links are added to complete the amplifier circuit.
Figure 3
Next, the PCB is firmly clamped to the working area to ensure that the "finger count" remains constant. The outlines of the areas coloured in red are then carefully scored with a craft knife and the unwanted copper lifted with a soldering iron. After cleaning with Isopropyl Alcohol, the PCB appears as in Figure 4. The result is a bit scruffy, but for an "A" model it is adequate.
Figure 4
The PCB is now ready for loading with components and this is best performed before fitting the PCB into the FLEXI-BOX as in Figure 5. With so much reflective surface, it is difficult to get a clear photograph, but the black surface mount components can just be seen.
Figure 5
The two links (with red insulation) are also fitted at this stage.