Defence firm Ultra Electronics has bought a US-based power conversion business to link up with its defence electronics arm, EMS.RFI, based in long Island, New York is an established manufacturer of high-voltage, power conversion subsystems including electronic filters, high voltage capacitors and pulse modulators. The deal has been agreed with RFI's parent firm, DGT Holdings, and will likely cost $12.5m.Rakesh Sharma, Chief Executive of Ultra, commented: "I am pleased that we have reached agreement to acquire RFI. It has strong market and technical synergies with EMS with which it will be combined to the benefit of both businesses."BS