Capacitance and transistor testing circuit – Elenco 3 1/2 Digit Cap. / Trans. Kit User Manual

Page 20

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background image

-16-

PARTS LIST - SECTION C

RESISTORS

Qty.

Symbol

Description

Color Code

Part #

r

1

R38

1.87k

Ω

1% 1/4W

brown-gray-violet-brown-brown

141830

r

1

R37

3k

Ω

1% 1/4W

orange-black-black-brown-brown

143030

r

1

R39

6.8k

Ω

5% 1/4W

blue-gray-red-gold

146800

r

1

R34

100k

Ω

5% 1/4W

brown-black-yellow-brown

161000

r

2

R35, R36

100k

Ω

1% 1/4W

brown-black-black-orange-brown

161030

r

1

VR2

200

Ω

Trim Pot

191320

Note:

Resistor tolerance (last band) of 5-band resistors may be blue instead of green.

CAPACITORS

Qty.

Symbol

Value

Description

Part #

r

1

C7

470pF (471)

Disc

224717

r

1

C10

.33

μ

F (334)

Mylar (small yellow)

253318L

r

2

C8, C9

4.7

μ

F

Electrolytic (Lytic)

264747S

r

1

C11

10

μ

F Electrolytic

(Lytic)

271015S

SEMICONDUCTORS

Qty.

Symbol

Value

Description

Part #

r

3

D3 - D5

1N4148

Diode (glass)

314148

r

1

IC2

LM324

Op-Amp

330324

MISCELLANEOUS

Qty.

Symbol

Value

Description

Part #

r

1

IC Socket 14-pin

664014

SECTION C

AC Voltage & Current Circuit

ASSEMBLE THE FOLLOWING COMPONENTS TO THE PC BOARD

Bottom Legend Side

R37 - 3k

Ω

1% 1/4W Res.

(orange-blk-blk-brn-brn)

(see Figure I)

D4 - 1N4148 Diode
D5 - 1N4148 Diode

(see Figure L)

C8 - 4.7

μ

F Lytic Capacitor

(see Figure B)

C10 - .33

μ

F (334) Mylar Cap.

(may be marked 334)

D3 - 1N4148 Diode

(see Figure L)

C7 - 470pF (471) Discap

Figure L

Stand diode on
end. Mount with
band as shown on
the top legend.

R38 - 1.87k

Ω

1% 1/4W Res.

(brn-gray-violet-brn-brn)

(see Figure I)

C9 - 4.7

μ

F Lytic Capacitor

(see Figure B)

R35 - 100k

Ω

1% 1/4W Res.

(brown-blk-blk-orange-brown)

(see Figure I)

R36 - 100k

Ω

1% 1/4W Res.

(brown-blk-blk-orange-brown)

(see Figure I)

D3

D5

D4

Assembled View

-19-

PARTS LIST - SECTION E

RESISTORS

Qty.

Symbol

Description

Color Code

Part #

r

1

R29

10

Ω

1% 1/4W

brown-black-black-gold-brown

121030

r

1

R28

90

Ω

1% 1/4W

white-black-black-gold-brown

129030

r

1

R45

150

Ω

1% 1/4W

brown-green-black-black-brown

131530

r

1

R27

900

Ω

1% 1/4W

white-black-black-black-brown

139030

r

1

R42

1.91k

Ω

1% 1/4W

brown-white-brown-brown-brown

141930

r

1

R43

4.3k

Ω

1% 1/4W

yellow-orange-black-brown-brown

144330

r

1

R26

9k

Ω

1% 1/4W

white-black-black-brown-brown

149030

r

1

R44

10k

Ω

1% 1/4W

brown-black-black-red-brown

151030

r

1

R47

11k

Ω

1% 1/4W

brown-brown-black-red-brown

151130

r

2

R40, R41

39k

Ω

1% 1/4W

orange-white-black-red-brown

153930

r

1

R46

76.8k

Ω

1% 1/4W

violet-blue-gray-red-brown

157630

r

1

R25

90k

Ω

1% 1/4W

white-black-black-red-brown

159030

r

1

R48

160k

Ω

1% 1/4W

brown-blue-black-orange-brown

161630

r

2

R49, R50

220k

Ω

5% 1/4W

red-red-yellow-gold

162200

r

1

R24

900k

Ω

1% 1/4W

white-black-black-orange-brown

169030

r

1

VR3

200

Ω

(201)

Trim Pot

191320

Note:

Resistor tolerance (last band) of 5-band resistors may be green instead of brown.

CAPACITORS

Qty.

Symbol

Value

Description

Part #

r

4

C12 - C15

.01

μ

F (103)

Mylar (large brown)

241017L

SEMICONDUCTORS

Qty.

Symbol

Value

Description

Part #

r

4

D6 - D9

1N4001

Diode

314001

r

1

IC3

LM324

Op-Amp

330324

MISCELLANEOUS

Qty.

Symbol

Value

Description

Part #

r

1

IC Socket 14-pin

664014

r

2

h

FE

Socket

664015

SECTION E

Capacitance and Transistor Testing Circuit

r

Attach the LCD to the PC board using the two 2.5
x 8mm screws. Use the top-mounting hole and
lightly tighten the screws. The screws will be
removed to assemble the next section.

Testing Procedure

1. Place the top label over the knob and turn the

range selector knob to an OHM scale position.

2. Connect the 9V battery to the battery snap.

3. Connect the test leads (red lead to V

Ω

CAP and

black to COM). Turn the meter on by pressing the
power switch.

4. Test the Ohms, Buzzer, and Diode functions

using the procedures below.

OHMs

- Using two or three different value resistors,

check each scale. Compare the kit meter readings

with another meter of known accuracy. If the tests
are not working, check the solder of the PTC.

Buzzer

- Set the selector knob to the Buzzer ( )

position. Short the red and black leads and the
buzzer should sound. If the buzzer does not sound,
check components R51-R58, PTC, C16, C17, and
the solder connections to the buzzer.

Diode

- Connect a diode to the test leads with the

correct polarity (see figure below). The meter will
range for 100 - 950.

5. Turn the meter off and remove the battery, top

label, and test leads.

6. Remove two display mounting screws and

display by unscrewing the two mounting screws.

DO NOT PROCEED TO SECTION E WITHOUT INSTRUCTOR’S APPROVAL.

COM

V

Ω

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