Richardson-based Eltek, the manufacturer of power supplies for the telecom industry, said this morning that it is selling its stake in Nera Telecommunications Limited (NeraTel), a Singapore-based provider of radio transmission, satellite communications, and other equipment to the Asian market. Eltek said it is selling its shares to Singapore Technologies Electornics Limited, as part of an effort to refocus on its power electronics business. The deal was worth approximately $65.54M.