Oakley 3031 - Manual (Page 14)

SPDT SW3, SW5
SPDT (on-off-on) SW4
DPDT SW1/2
Miscellaneous
Case, front panel, sockets, mains/power socket, wall-wart power supply/ transformer,
connecting wire, knobs, fuse holder (for mains supply).
Populating the PCB
Occasionally people have not been able to get their Oakley projects to work first time. Some
times the boards will end up back with me so that I can get them to work. To date this has
happened only four times across the whole range of Oakley PCBs. The most common error
with three of these was parts inserted into the wrong holes. Please double check every part
before you solder any part into place. Desoldering parts on a double sided board is a skill that
takes a while to master properly.
If you have put a component in the wrong place, then the best thing to do is to snip the
component’s lead off at the board surface. Then using the soldering iron and a small
screwdriver prize the remaining bit of the leg out of the hole. Use wick or a good solder pump
to remove the solder from the hole. Filling the hole with fresh solder will actually make the
hole easier to suck clean! You may lose the component in this process, but you are far less
likely to damage the PCB.
The 3031 issue 2 PCB is flashed with solder around the pads. This helps the soldering process
and keeps the board solderable for many years. Please note: this flashing is with solder that
contains lead. You should therefore wash your hands after handling the board and do not
place the board or the solder in your mouth. It is also recommended that for best results this
board is soldered with lead-tin solder.
I always use water washable flux in solder these days for my board manufacture. In Europe,
Farnell sell Multicore’s Hydro-X, a very good value water based product. You must wash the
PCB at least once an hour while building. Wash the board in warm water on both sides, and
use a soft nail brush or washing up brush to make sure all of the flux is removed. Make sure
the board is dry before you continue to work on it or power it up. I usually put the board
above a radiator for a few hours. It sounds like a bit of a hassle, but the end result is worth it.
You will end up with bright sparkling PCBs with no mess, and no fear of moisture build up
which afflicts rosin based flux. Most components can be washed in water, but do not wash a
board with any trimmers, switches or pots on it. These can be soldered in after the final wash
with conventional solder or the new type of ‘no-clean’ solder.
I have found that if you are using a very hot soldering iron it is possible to run your iron so hot
as to boil the flux in the ‘water washable flux’ solder. This is not a good idea as it can create
bubbles in the solder. If you prefer to have a fixed temperature iron, then it is best to get a
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