Need help with building current to voltage converter!!

[rumpfy]

Yes they did; and they were also known as 'moulded mud resistors'. Couldnt make them under controlled conditions, so they selected them into tolerance bands as you said. Capacitors too; the mica types were just the same.

 

[zonetrek]

Here is a brief of what I must do. Could anyone help me with a circuit that will work and the components that I will need please!

Design Project. Due date: 8 November 2013
Background
In factory instrumentation, process parameters such as pressure and flowrate are measured,converted to electrical signals, and sent some distance to an electronic controller. The controllerthen decides what actions should be taken. One of the main concerns in these systemsis the physical distance between the sensor and the controller. An industry standardformat for encoding the measurement value is called the 4–20 mA standard, where theparameter range is linearly distributed from 4 to 20 mA. For example, a 100 psi pressuresensor would output 4 mA if the pressure were 0 psi, 20 mA at 100 psi, and 12 mA at 50 psi. But most instrumentation is based on voltages between 0 and 5 V, not on currents.
Problem
The circuit in Figure1is a very accurate model of our situation. The wiring from the sensor unit to the controller has some resistance Rwire. If the sensor output were a voltage proportional to pressure, the voltage drop in the line would cause measurement error even if the sensor output were an ideal source of voltage. But, since the data are contained in the current value Rwire, does not affect the accuracy at the controller as long as the sensor acts as an ideal current source.
Figure 1. Sensor to controller connection
Design a current-to-voltage converter that will output 0 V at 4 mA and 5 V at 20 mA.
Write a report describing your design.
Tip – Use Opamps

This design converts 4 - 20 mA to 0 - 4V. hope it helps

Trek