Elenco AM Radio Kit - Manual (Page 13)

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Figure 6
Adjust your VOM to read 9 volts DC. Connect the
positive lead of the VOM to TP6 and the negative lead
to TP10. Turn the power ON and record the voltage at
TP6 here:
V1=________ volts.
Place resistor R4 across resistor R13 as shown in Figure
6.
The voltage at TP6 should drop to a lower value. Record
that lower voltage here:
V2=__________ volts.
Remove R4 from the circuit and move the positive lead
of the VOM to TP8. Record the voltage at TP8 here:
V3=__________ volts.
Once again, parallel resistor R13 with resistor R4 as
shown in Figure 6. The voltage at TP8 should also drop
to a lower voltage. Record the new reading at TP8 here:
V4=__________ volts.
Remove R4 from the circuit but leave your VOM
connected to TP8 for the next test. Turn the power OFF.
Since the DC GAIN equals the DC change at the output
divided by the DC change at the input, the DC gain of
this amplifier is (V1-V2)/(V3-V4). Your calculated answer
should be very close to 1.
If you do not have a generator, skip the following test and go directly to Section 1B.
DYNAMIC MEASUREMENTS
DC GAIN
GND
TP10
1M
Ω
Battery