A tube has its cathode connected through a resistor to ground. The resistor is labeled RK. In parallel with the resistor is a capacitor which is labeled CK. The grid of the tube connects to ground through a resistor labeled Rc. There are a pair of terminals on the left labeled input. The lower one connects to ground and the upper one connects to the grid of the tube. The plate of the tube connects through a resistor labeled Rb to a point labeled plate supply voltage, E b b. The plate also connects through a capacitor labeled Cc to the upper output terminal. This terminal connects through a resistor labeled Rcf to ground. The lower output terminal is grounded. End of verbal description.