4
Fold down C1, C2, and C3 at about a 45-degree angle, but not so far that they contact the nearby relay
pins. C1 should be folded toward K1, C2 toward K4, and C3 toward K2.
Solder C1-C3 and C10 from the bottom side to avoid damaging the relays. Trim the leads on the top.
i
In the following step, the installed height of the capacitors must be no more than 5/16" (7.5 mm).
The leads may be pre-formed so that the capacitors sit a small distance above the board. As long as the
installed height is below the limit specified, there's no need to straighten the leads.
Install the .01-µF capacitors ("103") on the top side of the board (C6, C4, C5, C7, C8, C11). They
should be seated as far down onto the board as possible (see above).
i
In the following steps, inductors L1 through L3 will be wound and installed.
There is no need to
adjust the windings to precisely match the inductances shown on the schematic.
Inductor L1 is wound on a T37-2 core (red) using 8" (20 cm) of #26 red enamel wire. To wind the
inductor, pass the long end of the wire through the core exactly 12 times
. Each pass through the core
counts as one turn.
The finished winding should look like the illustration below. Exact turns spacing is not
critical.
Spread out the turns of L1 so they occupy about 80-90% of the core’s circumference.
Cut L1's leads to about 1/2" (12 mm) long. Completely remove the enamel insulation from the leads
to within 1/8” (3 mm) of the core. The enamel wire provided can be heat-stripped using a small amount of
solder on the tip of your iron. Stripping using this method takes 4-6 seconds.
