
8.
Final Assembly of the
electro-music
Klee Sequencer
Putting It All Together
You’ve completed your front panel and the PCBs are all soldered up. Hopefully your
power supply is all ready to go, and you’ve either got the chassis or at least a good test
set-up going on there. It’s nearly time to put things together and put the juice to your
latest contraption.
But first…(there’s always a “but first”, have you noticed?)…..there are a few checks to
make. We need to make sure everything is as hunky-dory as possible before letting those
electrons run rampant through your well laid components, wires and circuit boards. You
should make sure they go where they should and don’t go where they shouldn’t. That
means a few simple checks are in order.
Inspecting the Digital Board
Before connecting the Digital Board to anything, a few simple checks will help to ensure
there are no “fatal” solder shorts. We’re really just looking to see that the power rails
aren’t shorted either to ground or to each other and they’re connected, at least nominally,
to the ICs at the right places. It’s not a total check, but it sure may head some problems
off at the pass. Checking the connections before the board is connected to anything else
will immediately tell you if a problem exists on the board
now
, before everything else
gets involved causing a problem to be much more difficult to trace.
Visual Inspection
Grab a magnifying glass and give the back of your board at least a cursory check – keep
an eye open for any solder bridges, connections lacking solder or having an inadequate
amount of solder, or relatively “dull” looking solder joints that may be cold solder joints.
If you spot any problems, take care of them now.
Flip the board over. Inspect your socketed ICs. Are the socketed fully? They’re not
sitting at some arcane angle above the socket are they? How about the pins – are all of
the pins in the socket? There aren’t any folded underneath or sticking out like a buck
tooth on the side of the socket, are there?
How about your transistors – do they line up with the silk screen legend? Is that
electrolytic cap’s positive lead really soldered to the positive pad? Are the diodes all
pointed in the right direction? Failure to spot defects of any of these types will certainly
cause you to tear screaming into the night (it’s always the night) when you power up the
Klee and begin bring-up and calibration.
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