ALMA Memo # 502

ALMA Band 6 Prototype Cartridge: Design and Performance

G. A. Ediss, M. Carter*, J. Cheng, J. E. Effland, W. Grammer,
N. Horner, Jr., A. R. Kerr, D. Koller, E. F. Lauria, G. Morris,
S-K. Pan, G. Reiland and M. Sullivan

National Radio Astronomy Observatory

*Institut de Radio Astronomique Millimetrique
300 rue de la Piscine
38406 St. Martin d'Heres, France

2004-06-21

This paper describes the design and performance of the initial Band 6 (211-275 GHz) ALMA cartridges. The incoming beam is coupled by 4-K reflecting optics to a scalar horn followed by an orthomode transducer. Each polarization is down-converted in a sideband-separating SIS mixer integrated with a pair of 4-12 GHz IF preamplifiers. Stringent thermal management and LO loss requirements are satisfied by using an overmoded stainless-steel waveguide between the LO triplers on the 100-K stage and the 4-K mixers. For ease of maintenance, all connections into the vacuum vessel are "blind mating."

View a pdf version of ALMA Memo #502.