The relay's primary appeal is its ability to do a lesser-switch's bidding but it's capable of so much more. Relays can be wired together to create very useful, simple, and utterly reliable networks.

Figure 1. Use the circuit in (a) to measure input bias current on the op amp’s noninverting input. Adding a loop amplifier in (b) keeps the op-amp stable for measurements on the inverting input. The ...

Anyone who assumes that passive or electromechanical components are simple is either naive or inexperienced. Even a basic, functionally simple component such as a high-power, milliohm current-sense ...