Elenco AM Radio Kit - Manual (Page 12)

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STATIC MEASUREMENTS
RESISTANCE TEST
You have completed wiring the Audio Amplifier. We shall proceed in testing this circuit. You will need for static
measurements, a Volt-Ohm-Milliammeter, preferably a digital type.
Adjust the Volt-Ohm-Milliammeter (VOM) to the highest
resistance scale available. Connect the VOM to pin 6 of
the IC as shown in Figure 6. Do not connect the battery.
The VOM should indicate a low resistance first and then
as C14 charges, resistance should rise to
approximately 4M
Ω. If you get a lower reading, reverse
multimeter leads. If you get a reading lower than
100k
Ω, check the circuit for shorts or parts inserted
incorrectly. Check C14 to see if it’s leaky or inserted
backwards. If you get a reading higher than 10M
Ω,
check for open copper or bad solder connections on all
components.
Figure 6
Figure 7
Set your VOM to read the highest possible current.
Connect the meter to the circuit as shown in Figure 7.
Make sure that the On/Off switch (SW1) is in the OFF
position.
While watching your VOM, flip switch SW1 to the ON
position. The VOM should indicate a very low current. Adjust your meter for a more accurate reading if necessary.
If the current is greater than 25 milliamps, immediately turn
the power off. The current should be between 3 and 15
milliamps. If you circuit fails this test, check that all parts
have been installed correctly and check for shorts or poor
solder connections. Turn OFF SW1.
POWER UP TEST
DC Amps
Amps COM V/ Ω
+
Ω
Amps COM V/ Ω
TP8