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Turn the PCBoard over so that you
are looking at the PLAIN side. From the drawing, find the locations of the
components. You will need to turn the PCB around so that it coincides with the
placement sheet. Remember that you are seeing the copper track through the PCB.
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Identify the values of the three
resistors by their colour bands and/or an ohm-meter. Bend the legs of the
resistors to a shape that will fit into their location holes. Push them
through and firm the resistor down against the PCB.
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The two transistors look the same but are
really quite different. Look for the identifying codes on the body of the
transistors. Offer the transistors into their positions with the flat on the
body the way round that the drawing indicates. Bend the legs to fit into the
holes. Push them in, but allow to stand high off the board.
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Spread the legs of the LED carefully so
they spring into its correct holes. Push the legs just through the PCB so the
LED stands high off the board. You should check that the small flat on the
flange at the base of the globe is the same way round as the drawing shows.
The LED is polarised - a semiconductor - and will not work if placed the wrong
way round. The flat is adjacent to the Negative (K) leg.
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The electrolytic capacitor is
polarised. An arrow is printed on the body pointing down the K (negative) leg.
Check the placement sheet for its polarity and location, push the legs through and solder.
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The disc ceramic capacitor is not
polarised so it can go in either way. Notice that the value of this capacitor
is coded on its surface. This one reads 103. The first and second numbers are
value digits and the third (3 in this case) is a multiplier, viz. indicates
the number of zeros following. This shows a value of 10000 -(1 + 0 + 000).
This value is always expressed in picafarads. Reference to a table will show
that this converts to 10 nanofarads, or 0.01 uF.
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These components may be soldered in place.
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Solder the battery snap with the red wire
to the positive rail, black to the negative rail. Cut the red wire and solder
the slide switch in series in that line, viz. one wire to a middle pole and
the other wire to one end pole on the same side of the switch as you soldered the middle one.
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Connect a battery and the flasher will
commence. The current draw is very small and the voltage is not critical, so
the light will flash for a very long time from the battery even when the
battery is almost completely flat. TRouble shooting will consist of
checking locations, polarity, and soldering. An alternative method of
connecting the flashing LED to a power supply exists if it is used as a dummy
(or a real) warning light that indicates that an alarm system is connected to
the car. A separate battery is OK but it will need to be checked frequently to
make sure the warning flasher is available when it is needed. The unit will
run from 12 Volts without any modification so it can be wired into the
electrical system and draw its current supply from the car's battery. To do
this you need to find a terminal on the car that has 12V available, when the
ignition key is turned off. A few minutes with a Voltmeter will help to find a
spot. The wiring then is simply to connect 12V positive to the positive pole
of the flasher, and connect the negative pole to an earth point on the car.
Virtually any metal part of the car is "earthed" so there is a wide choice
available. Use insulated wire for all connections.
IMPORTANT: (i) a LINE FUSE should be placed
in the positive wire, as close to the car terminal point as possible. Use a fuse
rated at no more than I amp. and preferably as loW as 500mA.
(ii) Position
the flashing unit,preferably enclosed in a non-metalic (plastic) box, so that
there is nopossibilit of any part touching a metal part of the car.
