The Micro Systems, Inc. Model 210 Data Link Transponder is an affordable yet highly reliable device used to assist in tracking manned vehicles. The transponder is mounted in a standard P-4 pod carried by aircraft requiring range safety or weapons testing tracking functions. The system is compatible with the Gulf Range Drone Control System (GRDCS). The transponder subsystems are packaged into four "modules" to accommodate the unique packaging requirements of the P-4 pod. The transponder incorporates the latest in solid state electronics design. Software satisfies the requirements of MIL-STD-2167A. An additional processor communicates with a NavStar XR5M-12 GPS receiver through three serial asynchronous data ports. The transponder receives RTCM-104 differential corrections via uplink messages. The transponder meets the requirements of MIL-STD-810 and will operate over the temperature range of -54°C to +71° C.