Class 4 Staff Materials

1
Electronics Merit Badge Class 4 Staff Manual
Name ____________________
6/22/01
2
Electronics Merit
Badge Class 1 AC Power Sources DC Power
Sources Voltage, Current and Resistance Build
Circuit with Light, Buzzer and Switch Class
2 Components - Passive and Active Ohms
Law Ohms Law Tool Kit Transistor Logic IC
Logic Class 3 Binary Logic Binary / Hex Tool
Kit LED Circuit Design Class 4 Solder
Theory Solder Practice Build LED Kit
3
Soldering
Safety NoteA Soldering Iron gets hotter than 300
F. Do not touch the soldering irons metal
parts or you will receive a third degree burn.
A good solder joint depends on the following
1) Solder iron must have a clean, well-tinned
tip. 2) Parts to be soldered must be clean. 3)
There must be a sound mechanical joint. 4)
Parts to be soldered must be well heated before
applying solder. 5) Wait approx. 5 seconds
after soldering to allow strong mechanical
joint to form.
1m 1m
4
Soldering
Iron
Iron
Wire
Wire
Solder melts at 310 F. So the wire and PC
board must be the same temperature for the
solder to melt on both items. Place soldering
iron so that it touches both the PC board and
wire. The heat from the soldering iron will
transfer to the PC board and wire.
PC Board
PC Board
Wrong way
Right way
Iron
Wire
PC Board
1m 2m
5
Soldering
When the board and wire are hot enough the
solder will flow and create a cone shape. If the
board is not hot enough the solder will be
rounded on the board creating somewhat of a ball.
The finishing solder should also be shiney.
Clip extra wire at board level.
Wrong way
Wire
Iron
After 3 seconds place the solder on the tip of
the iron, the wire and the PC board
all together. The solder should flow to
everything making a good connection .
Solder
PC Board
Wire
Iron
Wire
Right way
PC Board
Solder
PC Board
1m 3m
6
Un-Soldering
1) Unsolder two parts from the PC board. 2)
Use pliers to hold the component next to the lead
to be unsoldered. If the lead is held with
the pliers it will draw heat from the lead. 3)
Apply soldering iron tip to PC board and wire 4)
Either use solder wick or solder sucker to draw
solder off the board. Or simply pull wire
from PC board when hot. 5) The soldering
Iron will damage electronic components if
left on device for greater than 15 seconds. So
work quickly. Sometimes it helps to put
more solder on the solder joint to improve
the thermal conductivity. 6) Clean soldering
iron tip and keep it shiney.
1m 4m
7
Un-Soldering
Iron
Wire
Turn Soldering Irons on. Proceed to unsolder two
components.
With pliers, hold device close to lead that is
to be unsoldered. As heat is applied from
soldering iron, pull with pliers. With one side
out, do the same on other side.
PC Board
Iron
Pliers
PC Board
10m 15m
8
Soldering Kit
1) Place components into PC board in the order
recommended on instruction sheet 2) When
components are placed into PC board, bend leads
out slightly to keep parts from falling
out, when the PC board is turned over for
soldering. 3) Follow instructions as to proper
orientation of components.
PC Board
Clip wire at board

Red
LED Note Flat Edge
Black
1m 16m
9
Electronic 4-Bit Binary Counter Circuit Board Kit
Assembly Sequence
1) Place IC sockets in board, lay upside down,
then solder and cut. 2) Place all LEDs in
board, bend leads out and solder, then cut
leads. 2) Place Resistors in board, bend leads
out and solder, then cut leads. 3) Place
Capacitors in board, bend leads out and
solder. 4) Place Switch SW1 in board and
solder. 5) Place Switch SW2 in board and
solder. 6) Place Red wire on back of board and
solder. 7) Place Black wire on back of board
and solder. 8) Place Battery in box with foam
and cover with PC board
1m 16m
10
Electronic 4-Bit Binary Counter Circuit Board Kit
PC Board
Completed Kit
S1
S2
S1
S2
8
8


PUSH TO START

PUSH TO START

ON OFF
ON OFF
C2
C2
D8
D8
D7
D7
9
9
7
7
D9
D9
R1
R1
R2
IC2
R2
IC2
D6
D6
10
10
6
6
D10
D10
C1
C1
IC1
IC1
D5
D5
1
5
5
1
D1
D1
Electronics Merit Badge
Electronics Merit Badge
D4
D4
D2
D2
4
4
2
3
2
3
D3
D3
Kit parts PC board, 2 resistors R13.9M,
R2100K, 2 Capacitors C1.1uf,
C21uf, 2 ICs - IC1 14017, IC2 14046, 10
LEDs, 1 slide switch S1, 1
push button S2 and one 9 Volt battery clip and
battery.
1m 17m
11
Electronic 4-Bit Binary Counter Circuit Board
Kit Pass out kits and begin
S2
S1
8
PUSH TO START


ON OFF
C2
D8
D7
9
7
D9
R1
Solder first
R2
IC2
D6
10
6
D10
Notch
C1
Solder first
IC1
D5
5
1
D1
Electronics Merit Badge
D4
D2
4
2
3
D3
1) Place IC sockets, on PC board, turn board
upside down with IC sockets flat on board.
Make sure all leads are showing. First,
solder two adjacent corner leads on both sockets.
Turn board over and make sure socket is flat
to PC board. If not, holding PC board, press
socket that needs to be fixed, heat up corner
pin. Socket will move closer to PC board.
10m 27m
12
Electronic 4-Bit Binary Counter Circuit Board Kit
S2
S1
8
PUSH TO START


LED Note Flat Edge
ON OFF
C2
D8
D7
9
7
D9
Shorter Lead
R1
R2
IC2
D6
10
6
D10
Cut when soldered
C1
IC1
D5
No Space, LED against board
5
1
D1
Electronics Merit Badge
D4
D2
4
2
3
When soldering LEDs, do not leave the solder
iron on pads for more than 5 seconds, or you will
destroy the pad.
D3
2) Place LEDs on PC boards, flat side of
LEDs facing right, bend leads out, then
solder leads. After soldering cut leads
close to board.
10m 37m
13
Electronic 4-Bit Binary Counter Circuit Board Kit
C21uf

S1
S2
8
PUSH TO START


ON OFF
D8
C2
D7
9
7
D9
R2
R251K
R1
IC2
D6
10
6
D10
PC Board
C1
IC1
R1 3.9M
D5
5
1
D1
PC Board
Electronics Merit Badge
D4
D2
4
2
3
D3
C1 .1uf
3) Place Resistors R1 3.9M, (Orange, white)
then R251K (Green, RED, Yellow). Then
place capacitors C1 .1uf (disc) and C21uf.
2m 39m
14
Electronic 4-Bit Binary Counter Circuit Board Kit
S2
S1
8

PUSH TO START

ON OFF
C2
D8
D7
9
7
D9
14046
R1
R2
IC2
D6
10
6
D10
C1
14017
IC1
D5
5
1
D1
Electronics Merit Badge
Hot Glue
D4
D2
4
2
3
D3
1) Place Switches S1 and S2 in their
appropriate positions and solder. 2) Place ICs
into sockets after step 1 is complete.
2m 41m
15
Electronic 4-Bit Binary Counter Circuit Board Kit

Red
Black
9 V Battery
4) Connect the battery and turn on unit. 5) If
unit does not work have instructor review for
errors.
1) The battery wires will be soldered to
pads, but will not be pushed through hole. 2)
Heat up battery pads and melt a lot of
solder on pad. 3) While pad is hot place wire
to be soldered onto pad. The solder will
flow to lead.
2m 43m
16
Electronic 4-Bit Binary Counter Circuit Board Kit
Screw
Completed Kit
S1
S2


8
Screws
PUSH TO START
ON OFF
C2
D8
D7
9
7
D9
14046
R1
R2
IC2
D6
10
D10
6
Foam
C1
14017
IC1
9 v Battery
D5
5
D1
1
Electronics Merit Badge
D4
D2
2
4
3
D3
Box
Screw
1) Place Battery in bottom of box 2) Place foam
on top of battery 3) Place PC board and push
foam into box. 4) Use two screws on opposite
corners.
2m 45m
17
Trouble Shooting Circuit Board Kit
Front View
Back View
S2
S1


C2
D8
D7
D9
R1
R2
IC2
C1
IC1
There a few common causes for failure, they
are 1) No Power Battery wires reversed. 2)
LED comes on but not incrementing The IC are
put in backwards 3) LED does not work - LED
backwards. 4) LED are incrementing but some do
not working. The LEDs were soldered to high,
when pushed down after soldering have broken
the traces. A small wire can be soldered
between the pads.
Replacement wire
Trace Broken
Last resort call Al Mouton 512-303-2010