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Semiconductor parts familiarization, High resistance, Low resistance – Elenco AM/FM Radio Kit User Manual

Page 7: Transistor test (npn and pnp), Diode test

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TEST A

TEST B

TEST C

TEST D

TEST E

TEST F

Low Resistance

NPN

EBC

High Resistance

NPN

EBC

Low Resistance

PNP

EBC

High Resistance

Diode

Low Resistance

Diode

High Resistance

PNP

EBC

Ω

Ω

COM

Ω

Ω

COM

Ω

Ω

COM

Ω

Ω

COM

Ω

Ω

COM

Ω

Ω

COM

SEMICONDUCTOR PARTS FAMILIARIZATION

This section will familiarize you with the proper method used to test the transistors and the diode.

TRANSISTOR TEST (NPN and PNP)

Refer to the parts list and find a NPN transistor. Refer
the Figure J (page 16) for locating the Emitter, Base
and Collector. Using an Ohmmeter, connect the
transistor as shown in Test A. Your meter should be
reading a low resistance. Switch the lead from the
Emitter to the Collector. Your meter should again be
reading a low resistance.

Using an Ohmmeter, connect the transistor as shown in
Test B. Your meter should be reading a high resistance.
Switch the lead from the Emitter to the Collector. Your
meter should again be reading a high resistance.
Typical results read approximately 1M

Ω

to infinity.

Refer to parts list and find a PNP transistor, refer to
Figure K (page 16) for locating the Emitter, Base and
Collector. Using an Ohmmeter, connect the transistor
as shown in Test C. Your meter should be reading a low
resistance. Switch the lead from the Emitter to the
Collector. Your meter should again be reading a low
resistance.

Using an Ohmmeter, connect the transistor as shown in
Test D. Your meter should be reading a high resistance.
Switch the lead from the Emitter to the Collector. Your
meter should again be reading a high resistance.

DIODE TEST

Refer to the parts list and find a diode. Refer to Figure H
(page 16) for locating the Cathode and Anode. The end
with the band is the cathode. Using an Ohmmeter,
connect the diode as shown in Test E. Your meter should
be reading a low resistance. Using an Ohmmeter,

connect the diode as shown in Test F. Your meter should
be reading a high resistance. Typical results read
approximately 1M

Ω

to infinity for silicon diodes (1N4148).