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Anderson bridge

 Anderson bridge

It is modified Maxwell’s bridge in which the value of self-inductance is also obtained by comparing it with a standard capacitor.
This bridge is basically used for the precise measurement of inductance over a wide range of values. One arm of the bridge consists of an unknown inductor Lx with known resistance in series with R1. This resistance R1 includes the resistance of the inductor. C is the standard capacitor with r, R2, R3 and R 4 are non-inductive known resistances.

Advantages
1. Can be used for accurate measurement of capacitance in terms of inductance.
2. Other bridges require variable capacitors but a fixed capacitor can be used for Anderson's bridge.
3. The bridge is easy to balance from a convergence point of view compared to Maxwell's bridge in case of low values of Q.

Disadvantages
1. It is more complicated than other bridges.
2. Use more components.
3. Balance equations are also complicated to derive.
4. Bridge cannot be easily shielded due to additional junction points, to avoid the effects of stray capacitances.


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