A method for improving the manufacture and reliability of new, remanufactured, repaired or reconditioned Fire Control Radar APG-68 tactical radar systems (FCR) utilized in military aircraft and providing such units with extended useful life expectancies equivalent to or better than new of the FCR APG-68 unit high frequency, high voltage dual mode radar transmitters that are deployed in over 1000 state-of-the-art military aircraft such as the F-15, F-16 and F-18 fighter aircraft, and B-1 bombers. The novel method extends the mean lifetime of previously repaired and repairable FCR APG-68 tactical radar units and radar units and ageing transmitters from about 100 to a few hundred hours to about five hundred or more hours by the process of removing embedded moisture and absorbed moisture from the heterogeneous electronic components and preferably also removing contaminants from the heat transfer surfaces of the cold plates and heat exchangers in the FCR APG-68 tactical radar unit.