Fm Voltage; Transistor Current Test; Static Measurements - Elenco Electronics AM/FM-108K Assembly And Instruction Manual

STATIC MEASUREMENTS

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FM VOLTAGE

Connect your VOM as shown in Figure 28. Switch
the AM/FM switch to the FM position. Set your VOM
to read 9 volts DC. Turn the power ON. The voltage

TRANSISTOR CURRENT TEST

Connect your VOM to the circuit as shown in Figure 29.
Turn the power ON. The voltage at the emitter of Q6
should be about .7 volts. Record the voltage here:
V(Q6) = ________.
Turn the power OFF. If your answer is greater than 2
volts, check R20, R21, R22, R24, Q6 and the battery.
Figure 28
at this point should be between 7 and 9 volts. Turn
the power OFF. If you do not get this reading, check
R25, C24 and the battery voltage.
Figure 29
Since the current through resistor R22 is equal to the
current through transistor Q6, calculate the current
through Q6 as follows:
Current (I) = V(Q6) / R22
Your calculated answer should be between .0005
amps (.5 milliamps) and .0011 amps (1.1 milliamps).
Current (I) = __________.
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Battery
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