Accession Number:

AD0271988

Title:

250-500 MC LOW-NOISE TRAVELING-WAVE TUBE AMPLIFIER

Descriptive Note:

Corporate Author:

WATKINS-JOHNSON CO PALO ALTO CALIF

Personal Author(s):

Report Date:

1961-11-15

Pagination or Media Count:

1.0

Abstract:

Research continued on the development of a traveling-wave tube amplifier whose characteristics are as follows frequency range of 250 to 500 mc, at least 20 db gain with total gain variation less than 6 db, a 3 db or less noise figure objective 1.5 db at band center, power output of at least 0.5 mw and at least 75 db reverse attenuation. Using a high helix circuit and a very thin hollow electron beam resulted in a tube comparable in length 13 12 in. to its L and S-band counterparts with gain relatively constant over the operating band. The helix voltage is only 50 v and the beam current 0.3 ma. Cathode area permits a current density of 250 amp per square meter. Gains obtained when anode and helix potentials were optimized for best noise performance were of the order of 28 db 2 db over the octave frequency band. Noise figures less than 3.5 db over the octave band were obtained and the best single frequency noise figure of 2.4 db was measured. Saturated power output in excess of 0.5 milliwatt was measured with an input signal strength of -27 dbm. Reverse attenuation was measured and found to exceed 75 db over the operating frequency band. Author

Subject Categories:

Distribution Statement:

APPROVED FOR PUBLIC RELEASE