The device uses a microammeter with full scale deflection of 50 uA and with the resistance of 2 kilohms. The upper limit of the measuring range of the voltmeter is 1 V, and in the range of 0. 2. 1 V the measurement error due to the nonlinearity of the scale is less than 1% of the full scale range. By selection of the resistor R3 values the voltmeter

is calibrated at the middle of the scale, and by selection of the resistor R1 values - in the end of the scale. The linearization of the right side of the scale achieved due to the base current, which creates a voltage drop across the resistor R2. Because of this the gain of the rectifier are reduced to the end of the scale as required. If the measurement range is 3. 5 Volts and above, then it is better to use a silicon transistor in the rectifier. This voltmeter for the range of 10 V with the transistor KT3102D, has an error due to the nonlinearity of the scale at range of 1 V about 2%, and in the range of 2. 10 V - less than 0. 1% of the full scale range. Parameters of the circuit components are: R1 - 20 kilohm, R2 - 180 kilohms, and R3 - 62 kilohms. A voltmeter with a full-wave rectifier can be implemented with transistors of the same p-n-p type as shown in Fig. 2. The resistance of the resistors R4, R6 is roughly determined from the relation: R

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