MIL-DTL-38999 Coaxial, Concentric Twinax, and Triax Connectors
Connecting People & Technology

MIL-DTL-38999 with Coaxial, Concentric Twinax, and Triax Connectors

38999 quadrax can-clipAmphenol Connectors are ideally suited for the incorporation of shielded contacts for high performance interconnection applications. The circular family is built around MIL-DTL-38999 specifications, with Mil-approved and commercial styles offered. Normal operating voltage for circulars with power contacts only is up to 900 VAC (RMS) at sea level.

The MIL-DTL-38999 family offers these features for contact termination flexibility and Widest selection of insert arrangements that can incorporate:

  • Size 8 high speed Quadrax and Differential Twinax contacts for MIL-DTL-38999 Series III (specially modified to accommodate keyed contacts)
  • Transition adapters for use in attaching D38999 Series III connectors with high speed quadrax or differential contacts to PCB boards
  • Size 8, 12 and 16 Coax contacts
  • Size 8 and 12 Twinax contacts
  • Size 8, 10 & 12 Triax contacts
Wide selection of connector shell styles and sizes:
  • Scoop-proof recessed design in LJT-R, TV-R and SJT-R connectors provide protection for contacts
  • Standard power contacts are crimp rear release, qualified to SAE AS39029
  • Coax, Twinax, and Triax contacts employ the same retention system as power contacts, simplifying user substitution

CLICK HERE to view the insert arrangements most readily available patterns within the 38999 Circular Series. Consult a Amphenol Representative for other arrangements. In most cases, unless otherwise stated, size 8 and size 12 cavities can be filled with either coax, twinax, triax or power contacts.

Contact: High Speed

Sandra Wildenstein



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NEW! High Speed Contacts Guide

The NEW High Speed Contact Guide is easy to use and now your can sort by size, cable, impedance, series and type for a part number and termination instructions.

Termination Service Instructions

Contact Us

Amphenol Aerospace
40-60 Delaware Avenue
Sidney, NY 13838-1395



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