Every space application is unique and requires careful consideration before selecting the components to be used. A space environment subjects components and assemblies to severe environmental stress:

• Low earth orbit spacecraft subject solder joints, welds, brazements and mechanical connections to continuous hot/cold thermal cycling every 90 minutes. The manufacturing process must be carefully controlled per NASA STD-8739 requirements to assure consistent, reliable connections and assemblies. Solder connections must be 100% x-rayed to assure their integrity and reliability.
• There is no atmosphere so convection cooling does not occur. Excess heat must be removed by radiation, which requires the surface of the connectors to be an infrared emitter, or by conduction which requires a secondary heat sink.
• Certain materials “outgas” in the extreme vacuum of space which requires the designer to select materials and components that meet NASA requirements for Total Mass Loss (TML) and Collected Volatile Condensable Material (CVCM) to avoid contamination of optics and other sensitive equipment on board the spacecraft.
• Materials must be carefully chosen so that ionizing radiation does not destroy the connector or cable dielectric or the cable jacket.
• Multipaction failure (described in more detail herein) is a concern for high power applications.
• Intermodulation distortion (described in more detail herein) is a concern within systems where high power transmitting and low power receiving signals need to be carried simultaneously in the same transmission line.
• The manufacturing environment must be carefully controlled and the packaging materials selected to prevent dust and particles from accumulating on the components and subsequently contaminating the spacecraft.

Processes and controls used by Astrolab for procurement, manufacture, assembly, soldering, x-ray, inspection and testing have been certified by NASA for use in spacecraft applications. Astrolab has the design, manufacturing, testing and applications experience and expertise to supply your needs for passive microwave devices for use in any space environment

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