Assembly Steps - Ramsey Electronics WCT3 Manual

ASSEMBLY STEPS

Surface Mount Semiconductor Installation
1. Orient the board as shown in the board layout diagram on page 1
2. Install U1, the LF347 IC( marked LF347). Notice that there is an in-
dented dot near one corner of the IC. This indicates the location pin 1 and
the IC must be installed so this dot is to the upper left near the small white
dot printed on the circuit board. Place the IC on the board and make sure
all the leads on both sides of the IC align with all the solder pads on the
board. Note that once more than one lead is soldered it will be difficult to
reposition the IC if the placement is incorrect. Because of this we suggest
that you first carefully solder only one of the corner leads and then make
sure all other leads are aligned before soldering all other connections.
3. Install U2, the LM324 IC, (marked LM324), following the same instal-
lation procedure used in step #2 above for the LF347.
Locate the two(2) Resonator coils, L1 & L2, marked 715. The connections for
these coils are under the device body. To install them first apply a small coat-
ing of solder on each of the 4 pads on the circuit board. Try to keep the sur-
face as level and flat as possible or it will be difficult to properly place the coil.
Once the pads are coated place the coil so it is centered inside the white
printed white lines taking note that one of the corners is 'marked' at a 45 de-
gree angle. This will allow a portion of each pad to be visible so you can melt
the solder which will also heat the coil connection and the solder will flow onto
the coil. When the solder flows evenly apply a little more solder and remove
the soldering iron. Solder one of the smaller pads first, check alignment and
then solder the remaining pads. You may find it takes a little more time on
some pads because of the copper connected to the pad.
4. Install resonator coil L1.
5. Install resonator coil L2.
Locate the 3 BAV99 diodes, marked A7 or A7X, D2, D5 and D9.
6. Install D2 located just above the preinstalled L1 resonator on the left
side of the board. Again solder only one lead first, check alignment, and
then solder the remaining leads
7. Install D5 located to the right of U1 near the edge of the board.
8. Install D9 located just above D5 near the edge of the board.
Now we'll start installing the resistors and capacitors. We will install each
value as a batch to keep from mixing them up. Unless otherwise instructed all
these components can be installed in either direction as long as they are
placed within the areas indicated for each.
WCT3  14