The Denver businessman offered $321.9 million to acquire the remaining shares of Spectradyne Inc., the nation's largest supplier of pay-per-view movie systems to hotels. Davis made his $37-per-share offer for the rest of the company's outstanding common shares after the market closed. Earlier this week, Davis disclosed in Securities and Exchange Commission filings that he had acquired 7.3% of Spectradyne, based in Richardson, Tex. Spectradyne's stock closed at $40.37 1/2 per share, which was well above its price of $22.50 when Davis began buying stock. The company has 9.4 million shares outstanding. Unless an agreement in principle or definitive agreement is worked out by May 14, he will withdraw the offer, Davis said.