Ramsey Electronics FM100B, Instruction Manual

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FM100B
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20
10A. Install DISP4, the other 10 segment bargraph display. Make sure to
align this in the same way as before and solder all 20 pins.
11A. Install DISP1, one of the two digit displays. Notice how there is no
indication of pin 1 on these. You want to orient the display so that the
lettering on the one side faces towards U11. It should be positioned so that
the Decimal Point is closest to U11. Solder all 18 pins.
12A. Install DISP2, the other two digit display. Again orient the lettering
towards U11 before soldering all 18 pins.
13A. Install D7, one of the small red LEDs. Notice that if you look straight at
the LED there is a flat side. This indicates the Cathode side of the LED. The
Cathode side is also indicated by the shorter of the two leads. Make sure to
install the flat side or the shorter lead in the same way as shown in your
diagram. They only light up if they are installed correctly. Before soldering
though, this and the next LED are the only parts that we do not mount flush
to the PC board. In this case we want to mount them so the lens of the LED
is at the same height as DISP1 and DISP2. These LEDs will eventually be
lining up with holes in the front panel. Once the height is set, bend the leads
to hold the LED in place, then solder. (
Note: Some builders prefer to
temporarily install the front panel on the case and line up D7 and D8 flush
with the front panel overlay. This increases the viewing angle of the indicator
when it is tight to the display.)
14A. Install D8 in the same fashion, making sure it is at the same height and
orientation as in the previous step.
Now would be a good time to check all of your solder connections for opens
and bridges on the back side of the board. The next few steps will be to install
the components that are mounted on the rear side of the front panel (two
jumper headers and two electrolytic capacitors). These parts are shown in light
gray instead of black on the Display Board Parts Layout Diagram.
15A. Install J11, a five pin jumper block (shorter leads soldered onto the
board). Again make sure you are putting them on the opposite side of the
board from where the rest of the parts have been located. This jack is where
the numeric display gets its power and the data for display values.
16A. Install J10, another five pin jumper block. This is where the power for
the bargraphs is applied and the signal levels for the bargraphs are sent for
display (mount it on the backside like J11).
A
K
1/4"
S ame height
as D S 1+D S 2