| For control of signal levels, particularly in low-frequency circuits, some kind of elec-tronically variable resistance is often required. In...
| For control of signal levels, particularly in low-frequency circuits, some kind of elec-tronically variable resistance is often required. In...
| There are many cases where it is useful to be able to get rid of sp_urious mains (50 Hz) interference. The simplest way of doing this is...