FM30
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FM30 PC BOARD ASSEMBLY STEPS
The FM30 is one of our larger, more complicated kits, however, if you follow
the steps closely you will find that it will go together smoothly. We will start
with the larger main PC board. We’ll have a working kit in no time!
1. The first thing you’ll have to do is to separate the front panel PC board
from the main PC board. Simply grasp the two boards and carefully snap
them apart.
2. Once you have the boards apart you’ll notice that there are little tabs
left where the boards used to be connected. You’ll want to trim these
down so that the board fits into the case correctly. Take your sidecutters
and nip off the excess board material, then take some sandpaper or bor-
row your wife’s emery board to sand down what’s left. But don’t tell your
wife that we told you to borrow the emery board!!
3. Now we’ll install a surface mount part but don’t worry, it’s not a difficult
one. We’ve placed all the tough ones on the board for you and left you the
regulator VR1, LM940CS-12 12VDC low dropout regulator. The first thing
to do is to tin the large pad that the body of the regulator will sit on. Tin-
ning means to melt a small amount of solder on that pad. Next, place the
part on the large pad so that the legs line up with their individual, smaller
pads. Once you’re sure everything is aligned properly, solder the three
leads of the part. With those soldered, you’re going to solder the large
metal tab on the part to the pad you tinned earlier. Hold your iron down on
the large metal tab on the regulator while pressing it onto the tinned pad
until you see the solder flow. That should hold things in place and should
also provide a heatsink for the part.
4. Install U5, the LMC6484AIN quad rail to rail opamp. We’re starting
with the ICs so that you can use the PC board to keep the part flat until
you solder it. Follow the dot or notch on the chip and match it to the silk-
screen marking or Parts Layout Diagram for proper placement. Make sure
that all the pins are through the board and none are bent under or sticking
out, then slightly bend two corner pins to keep the IC from falling out when
you flip the board over. Check to be sure that the part is flat to the PC
board, then solder all 14 pins.
5. Install U2, an MCP42010-I/P dual 10K digital pot. Follow the notched
end for correct placement and make sure you solder all the pins.
6. Install U4, the LM6482 dual rail to rail opamp, following the same pro-
cedure as the last two ICs.
7. Install the socket for U1, the 28 pin microcontroller IC. Install the
socket the same way you installed the ICs in the above steps, making
