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A10. Study the PC board, locate the triangular set of 3 holes for VR2
(type 7805), and insert VR2 so that the flat metal tab side is toward the
center of the board. Press VR2 in as far as it will go, solder and trim.
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A11. Near VR2, install C100, a 4.7 or 10 uf electrolytic, oriented for
correct polarity.
Stage A PROGRESS TEST:
The power input circuitry is completed and can be tested before proceeding.
Perform the test as follows:
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1. Make sure a 1 amp fuse is installed in the fuse holder.
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2. Connect the fused (+) and black (-) wires to a 12-volt battery or
power supply (12-15 volts DC).
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Connect the black (-) lead of a DC voltmeter or VOM to the ground
plane of the PC board.
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Study the PC board and locate the three points marked +12V, +8V and
+5V. (These connections are provided for convenience in later
modifying or experimenting.)
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With the power switch turned on, you should get meter readings of
+12V, +8V, and +5V respectively. (If your meter probe does not have a
fine enough point to make solid contact inside the holes at these 3
points, simply study the multi-color PC board illustration and look for
+12, +8 and +5 volts DC on PC board traces that lead to the 3 voltage
points.)
After you are satisfied that the power input circuitry is working correctly,
disconnect the 12 volt source.
WIRING THE PACKET I/O CONNECTION:
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A12. Press J1, the Packet I/O DIN connector into position. Before
soldering, make sure that the bottom of the jack is perfectly flat against
the board. It is best to solder only the middle pin first, check for
straightness, and then solder the other 4 or 6 points. (DIN jack styles
may vary; your jack may have simply the 5 connector pins, or 2 extra
pins for mechanical stability. Either style fits your PC board.) Directions
for installing hardware or unusual parts often require extra written detail.
You've just been through a lot of that in this stage.
The following steps are more typical of how many upcoming installation
directions will be given:
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Stage A: ASSEMBLY STEPS
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A1. Strip 1/8" of insulation from the heavier-gauge black wire, insert and
solder in the GROUND hole. This connection may be soldered on the
TOP side of the board as well as the solder side.
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A2. Strip 1/8" of insulation from the in-line
fuse wire and solder it to one of the S1
switch lugs of the volume control (R7).
The switch lugs are the two outermost
lugs of the 5 lugs.
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A3. Strip 1/8" of insulation from each end
of the heaviest gauge 1 conductor wire
remaining in your kit. Solder one end to
the other switch lug on R7 and the other
end to the PWR point on the PC board. MAKE SURE that ALL strands of
this wire are neatly inserted and soldered in the hole. Any stray strand
will cause a direct short when it touches the ground plane.
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A4. Install L20, the 500 uH noise filter inductor. It is the large cylinder
shaped component with wires coming from each end.
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A5. Install C42, 1500 uf, the first (and largest!) of the electrolytic
capacitors. The (+) side must be oriented as imprinted on your board,
toward L20.
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A6. Install C95, a 4.7 to 10 uf electrolytic.
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A7. Select D18, the 1N4002, the largest of the diodes used in your kit. It
has a black body with a gold band on one end. Notice the band towards
one end designating the cathode. This diode MUST be installed with its
ANODE in the ground hole nearest the back of the PC board. Solder the
anode end now, letting the diode body stand vertically on the board.
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A8b. Gently bend the cathode wire into its hole, pull it through so that it
is as short as possible with the diode standing vertically. Solder and trim
excess wire. NOTE: this is the basic method for installing all upright
parts.
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A9a. Voltage Regulator VR1 (type 7808 for 8 volts) is mounted with its
metallic back flat against the ground plane, secured by the small
machine screw and nut supplied. Identify VR1 correctly without mixing it
up with its 5-volt counterpart (VR2).
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A9b. Insert the 3 VR1 leads into the triangular set of holes while gently
bending the body back towards the board so that the mounting holes line
up. Secure VR1 to the board with the screw and nut. After VR1 is
mounted flat, solder and nip the 3 leads.
FUSE
PWR
VOLUME
IN
OUT
GND
