* Rene H. Caron has joined Alpha...

* Rene H. Caron has joined Alpha Microsystems as vice president of sales and marketing. He succeeds Douglas J. Tullio, who was earlier promoted to president of the Santa Ana computer company. Caron was formerly a principal with the South Coast Group, a corporate communications, investor relations and marketing firm in Tustin. Before that, he was with General Automation Inc., most recently as vice president.