Gresham Power Electronics (Salisbury, UK), a subsidiary of Digital Power (Fremont, CA), has received orders exceeding $1,000,000 from EN Bazan for various power converters used on four F-100 frigates belonging to the Spanish Navy. The principal Gresham product is a 15kVA transformer rectifier unit (TRU) which provides dc power to service and start the vessel's Sikorsky SH-60 helicopter.The F-100 frigates are the latest Spanish Navy vessels to be fitted with Gresham equipment. Gresham has already supplied both ac supplies and the main dc distribution for four Spanish Navy mine hunting ships built in Cartegena, Spain.