(ABC NEWS) - The Vatican prepared the Sistine Chapel today for the election of a new pope by installing electronic jamming devices, floorboards to protect the historic chapel's marble floors and the stove that will eventually send up white smoke signals announcing the new pope's election.

Those preparations, plus two tardy cardinals, meant no announcement yet of when the conclave will start.

"It is unlikely we will set a date today," the Rev. Thomas Rosica told reporters. "For one thing, the chapel is not yet ready."

Workers have started installing floorboards to protect the chapel's marble floors as well as the stove to burn the ballots and communicate the election results.

The Vatican spokesman noted that jamming devices are now being installed in the chapel, but not under the floorboards as previously reported.

"They won't work if you put them there," Rosica said. He described the jamming device "more like a shield on an airplane" installed high up on the walls.

The cardinals are also still waiting for a few colleagues. As of Wednesday, voting cardinals from Vietnam and Warsaw had yet to arrive in Rome. But as of today 113 of the 115 cardinals expected to participate in the conclave were here and sworn to secrecy.

Today cardinals participating in closed-door deliberations ahead of the conclave adopted a five minute rule to limit the length of speeches. So far, 51 cardinals from five continents have addressed the group.

At least one participant reportedly expressed his frustration with some of the speeches.

"No matter how brilliant you may think your speech is, do we really need it?" Nigerian Cardinal John Oneiyekan told the National Catholic Reporter.

The cardinals will be giving no more interviews or press conferences from now on. According to the Vatican press office, they have collectively decided that it is in the best interests of the process to adhere to a gag order.

ABC NEWS