Elenco Electronics AM/FM-108CK, Сборка и инструкция по эксплуатации

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Figure 4
Figure 3
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TP15
COM
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V
A
Amps COM
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STATIC MEASUREMENTS
Wear safety goggles during all tests in this manual.
POWER TEST
For all measurements, connect your equipment GND to
circuit GND TP15. Set your VOM (Volt-Ohm-Millimeter)
to read 2 amps DC. Connect the meter to the circuit as
shown in Figure 3. Make sure that the volume control
is in the OFF position (turned fully counter-clockwise).
While watching you VOM, turn the volume to the ON
position (rotate clockwise until a “click” is heard). The
VOM should indicate a very low current. Adjust your meter for a more accurate reading if necessary. If the
current is greater than 20 milliamps, immediately turn
the power OFF. The current should be less than 10
milliamps. This is the current drawn by the battery
when no input signal is present (the “idle current”). Turn
OFF the power. If your circuit fails this test, check that
all of the parts have been installed correctly, and check
for shorts or poor solder connections.
OUTPUT BIAS TEST
Put the battery into the holder.
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