In 2003, DTI installed an upgrade to the X-band radar transmitters in both the Cobra Judy X-band system (the large dish on the USNS Observation Island) and the Gray Star system, located onboard the smaller USNS Invincible. For the Cobra Judy X-band system, DTI built the complete transmitter, including all electronics from ship power, to modulating the two, 100 kW average-power TWTs located behind the dish .The system includes three 100 kW switching power supplies, a series opening switch, and a grid modulator driving two TWTs.

In October of 2006, DTI completed an upgrade of the ship's phased-array S-Band transmitter. The upgrade builds substantially upon the recently completed COBRA JUDY X-Band radar transmitter. It maximizes the commonality of spares, support, and operations between these two systems, and replaces the highest failure rate items in the existing transmitter.

A Product Brief in PDF format describing the CJX upgrade can be dowloaded here. A description of the CJS transmitter project can be found here.

USNS Observation Island

CJX Transmitter Installed