Instruction manual

DDF1  24
105. Temporarily fit the circuit board into the case top, and carefully tip the
board and case over and allow the LED’s to fall into their respective holes
in the case.
106. With the 19 LED’s correctly oriented and set to the correct height,
solder into place while the circuit is in the case top. Be carefuf and don’t
touch the hot soldering iron to the case top. Doing so not only makes boo
-boos in the case but is also smelly.
107. Install J1, the 2.1mm DC input connector. Notice that this mounts on
the “component side of the circuit board and the solder leads push
through the circuit board to protrude through the solder “pads” for connec-
tion. Be sure to push it firmly onto the circuit board as the alignment of
this part is important in getting the case holes to line up with the part. Sol-
der all three leads; don't be afraid to use enough heat to flow the entire
connection and fill the holes.
108. Identify and install J3, the miniature audio input jack. Gently “rock”
the component into place firmly onto the board before soldering.
109. In the same manner, identify and install J2, the DB 9 connector,
which will output the switching control voltage to the antenna switch. This
jack is a large plastic and metal connector with the board and cable con-
nections at a right angle to each other. Be sure that the connector fits
firmly to the printed circuit board. Solder all connections as well as the two
large mounting tabs. The tabs will require a lot of heat to get the solder to
flow evenly. Don’t be afraid to get them really hot.
The main board assembly is complete! You are that much closer to a function-
ing Doppler DF system. Take a break...you have accomplished the biggest
“chunk” of the kit. We also recommend you check over your work so far and
make sure there are no missed or bridged(slobbered) solder connections and
that all components are installed properly and the correct values. The next
steps will assemble the antennas and switching system for the DDF1.