A series of human errors caused a 40-minute failure in the city's police radio system July 22, according to a report submitted today to City Council by the Nutter administration.

The report also said the problem-plagued Motorola system will cost $40 million to upgrade - almost as much as it cost to install in 2002.

The Motorola system has been hobbled by dozens of malfunctions, from system-wide crashes of almost an hour to momentary glitches.

The system failure last summer enraged Police Commissioner Charles H. Ramsey, who called the problem "unacceptable." Councilman Frank Rizzo, who sits on the public safety committee, demanded an explanation from the city and Motorola.

The report, written by Frank Punzo, the city's deputy commissioner of public property, said on the night of July 22, the radio system became overloaded and switched - as it was designed to do - from one controller to another.

Earlier that day, Motorola had conducted routine maintenance on the controller. A technician, however, had not entered the correct settings for the component.

"As a result, when the secondary controller was required to function, it failed to do so . . .," the report said.

In the span of 40 minutes, a technician corrected the settings and the system returned to operation.

The report said the police dispatch center was still able to communicate with officers on the street using back-up modes. But dispatchers were not skilled in how to use the back-up equipment.

The report said corrective steps include:

Revising maintenance procedures;

Training and testing dispatchers to be completely familiar with back-up components;

Improving the performance of Motorola's technical staff;

Placing replacement controllers on standby to avoid delays in service.

The report said the radio system, installed in 2002, is already outdated.

The current maintenance agreement with Motorola expires in June 2010. The city is considering an extension, but "it does not appear to be the most desirable option," the report said.

The 800-megahertz digital radio system, which has cost the city about $62 million to install and maintain, is no longer manufactured by Motorola and replacement components may no longer be available.

The city could decide to scrap the Motorola system and go with something else. But that process could take "a minimum" of five years to accomplish, the report said.

"It is clearly apparent that we are faced with a number of difficult decisions, particularly in light of the current fiscal constraints being experienced by the city," the report said.

"It's an antiquated system and now we need a new one," Rizzo said.

Rizzo said the type of technology used by Motorola is still used in other parts of the world. He said the city might want to consider seeing if it can sell parts of its current system to get a better one, "like a trade in."