Modifies a noun

• valve: And it's got a real, old-fashioned triode valve glowing away on top.

• tube: The book includes some fascinating photos - including that of HP's founders with Lee De Forest, the triode tube inventor.

• section: The triode section of this valve acts as the local oscillator in a tuned anode feed-back circuit, and it is parallel fed.

• grid: The grid and cathode act as a diode, with the triode grid functioning as the diode ' anode ' .

• squarer: In Chapter 4 ( p 88 ) we saw that the output from a triode squarer is not a perfect square wave.