In electronics the Carey Foster Bridge is a bridge circuit used to measure low resistances, or to measure small differences between two large resistors. It was invented by Carey Foster as a variant on the Wheatstone Bridge. He first described it in his 1872 paper "On a Modified Form of the Wheatstone Bridge, and Methods of Small Resistance Measurement" (Telegraph Engineer's Journal, 1872-1873, 1, 196).
Caution in F.6 Physics Experiment
1. Do not short circuit any battery box or power supply.
2. Use the component holder to connect small electronic components.
3. Set R to maximum before connecting the potentiometer, rheostat, resistance box in the circuit.
4. Turn the meter off by adjusting the selector in any range but NOT on the Ohm scale after use.
5. Do not change the range of the Meter when connected.
6. Do not touch any optical part (eg grille, groove slide, and lens, etc.) of the optical instrument.
7. Be careful and do not scratch the optical instrument. Remember to pack it after using it.
8. Do not hit the pins on the wooden board. Secure the pins by finger pressing only.
9. Set the amplitude of the signal generator to the zero output before turning it on and off.
10. Leave the CRO all the way to the end of the experiment. (When it is not in temporary use, simply decrease its intensity.
11. Turn the signal generator amplitude to zero when not in use.
12. Check the amplitude of the signal generator setting in the zero position whenever the signal generator is turned on or off.