Filament Check

When measuring voltage, wrap tin foil around the top of the negative probe. Then press the foil against the wire with your finger.

Fig 1: Pressing Tin Foil Against Heat Wire
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Attach probe circuit tester (in Volt range) to middle portion of each filament.

Fig 2: Checking Filament Circuit
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If a filament is burned out, circuit tester registers 0 or battery voltage.
To locate burned out point, move probe to left and right along filament. Test needle will swing abruptly when probe passes the point.

Fig 3: Identifying Burned Out Point
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