Small Wonder Labs
PSK-20 Transceiver Kit 03/09/10
2000
11
Building instructions:
All parts installed on the PC board should be fully
seated unless otherwise noted in the assembly text..
Static-sensitive Components:
Components noted in bold in the assembly text are
static-sensitive. The following general precautions
apply:
•
Keep these parts in the antistatic bag until you're
ready to install them and handle them no more
than necessary.
•
Ideally, you've got a grounded-tip iron, but if not-
After the part is installed on the board and before
soldering, touch the iron tip to shack ground (if
available) or to a PC-board ground point.
•
Avoid placing these components on paper.
•
Diode Installation:
Some of the diodes are bent for "upright"
installation on the board. Installation polarity is as
shown below. Be sure to note the orientation of the
silkscreened circle on the board and install the diode
body over this hole. The cathode (banded) end of the
diode is oriented at the top. For diodes which are
installed 'lying down', match the banded end to that
shown on the silkscreen.
Installation- Pictorial
Diode-Schematic
banded end
is cathode
Component
Silkscreen
•
Resistor installation:
Many resistors are likewise installed in 'hairpin'
fashion. As with the diodes, try to match the mounting
orientation shown on the drawing. (If mounted as
shown you've got better troubleshooting access to
circuit points from the top side of the board.)
Orientation of color bands on resistors and other
nonpolar devices is not critical.
•
Installing IC sockets:
The "notch" or dot at one end should be oriented as
shown in the pictorial drawings. Doublecheck
orientation before soldering.
A suggestion
- solder
down two opposite corners of each socket, and then go
back and press a fingertip on the socket from
underneath while reheating both connections in turn.
You may then solder the remaining pads. This
precaution ensures that the socket is well-seated on the
PC board.
Recommended Assembly sequence:
I've specified the sequence detailed in the pages
which follow, but there's nothing sacred about the
order in which the board is populated. Some parts are
best installed in a particular order, as noted within each
group's instructions.
Directions for winding toroids are found within each
group's assembly instructions.
'The Real Men's Corner:
'
This is for the folks who don't read instructions- you
know who you are! Be aware of the following:
- Crystals and the driver transistor (Q10) should be
stood slightly (0.5 to 1mm) above the printed-circuit
board to prevent shorts from case to ground.
Here's one other tip if you prefer to work only to the
schematic and master pictorial:
Stuff only a few parts at a time (3-4 pieces). If you try
to add too many parts at once between soldering
operations, you may lose track and wind up with
missing solder joints! Once you've stuffed the parts on
the board, bend the protruding leads slightly outward
to keep them in place while the board is inverted for
soldering.
