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The Model 414A Autovoltmeter is used to accurately measure dc volts and ohms with immediate, automatic range selection. Operation is simply "touch and read." Automatic, overload protection circuits insure that the instrument will not be damaged by an overrange voltage before upranging can occur. Both range and polarity are displayed in illuminated characters above the meter. In the AUTO mode, a downrange to the next lowest range occurs when the measured voltage or resistance falls below 25% of full scale; and an uprange to the next highest range occurs when the measured voltage or resistance rises above 96% of full scale. A HOLD mode provides manual downranging, a step at a time, using the DOWNRANGE switch and also adds a noise Filter to the input. When measuring voltage in this mode, an automatic uprange to the 1500 v range will occur if the measured voltage exceeds full scale by 40%. On resistance measurements in the HOLD mode, upranging will never occur, even when the measured resistance becomes infinite, such as when the probes are removed from a resistor.