User manual
51
2 Design and Assembly
It is important to sufficiently warm the contact to be
soldered and the soldering pad before you apply any tin-
solder. It is best to place the tip of the soldering iron so that
the contact of the component and the soldering pad are
heated simultanuously.
Aer that, you solder in the LEDs. From the bottom
side of the circuit board (the one without components!),
push the LED leads through the designated holes. The
blue LED is soldered in next to C 6, the white one next to
IC 3. Make sure of right polarity of the LEDs. The longer
LED lead (anode) has to be connected to the soldering pad
marked as “+“, the shorter one (cathode) to the soldering
pad marked as “-“. The LED leads are pushed through the
board as far as possible and bent apart a little.
Use a wire cutter to shorten the leads approx. 3mm
above soldering pad level, and solder them. As with any
semiconductor components, LEDs are affected by heat.
Thus you have to solder them speedily. When you do not
have much experience in soldering, it is best to wait a
Fig. 2.2:
Pin header.
Only the middle
two pins may
be connected
with solder.