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|Fenwal 10k NTC thermistor data (plus surplus thermistors)|
Using only four resistors with standard 10% values with 10,000 ohms being the lowest value, design a high impedance, DC-coupled amplifier with four gain settings of 5, 10, 20, and 30 dB (± 0.2 dB). Assume the resistors are exact values but they must be from the 10% family of values (10,12,15,18,22,27,33,39,47,56,68,82). The design must use only the four resistors, one op-amp and one 4-position rotary switch of any type and configuration. Misc. other ancillary parts that do not directly relate to the performance like power supply bypass capacitors are fine. A dual voltage supply is assumed.