Traveling-wave tube limiters

Good broadband microwave limiters can be built by appropriately modifying conventional traveling-wave tubes. For example, several S-band limiters were developed and are now in use in which the output power can be held constant to within db over a range of input of approximately 50 db and over a 700 mcs frequency range. This was done by using commercially available traveling-wave tubes. All the necessary modifications were made from outside the tube envelope. No constructional changes involving tube parts within the envelope were required.