Transients who frequent Pershing Square in downtown...

Transients who frequent Pershing Square in downtown Los Angeles expressed more than passing interest when a crew of workmen arrived there this week to string lights and holiday wreaths--and to erect a full “shantytown” of tents and makeshift cardboard shacks.

Was this the city’s new shelter program?

Well . . . no.

The builders turned out to be from Aaron Spelling Productions, which is filming part of an ABC Movie of the Week called “Three Kings.”

Spelling spokeswoman Lynn Morgan said the film is a Christmas story, and praised the “friendliness and cooperation” of the park’s regulars in staying out of camera range and keeping quiet during the crucial minutes while the cameras and sound reels are rolling.

Movie companies are not Santa Claus, however.

Guards were posted to keep the real homeless population from moving into the set overnight.

Nineteen Los Angeles County multimillionaires were included in Forbes magazine’s annual listing of the 400 richest Americans--but none of them were among the “top 50”--among whom the first 49 are billionaires.

The county’s richest: Investor Kirk Kirkorian (No. 51 on the list, with estimated assets of $950 million).

Parked in a prime location--between the County Courthouse and the Law Library at the downtown Civic Center--the hot dog vendor was doing a prime business: Hot dogs $1.50 . . . and T-shirts (“I Survived L.A. Earthquake”) $5.

(But neither price includes bicarb.)

John Khadivi said he sleeps under his own personal earthquake insurance--but it’s no mere umbrella policy.

A structural engineer, Khadivi has invented something that he calls “the beautiful solution to a major California problem,” and he placed it on display this week at a furniture store in Santa Monica.

“When I was 9 years old,” he said, “I was in an earthquake, and I wondered what would happen if our house collapsed while I was asleep. So last year I finally did something about it.”

What he did was build a steel canopy bed that he says is designed to withstand the tons of falling debris, like beams and plaster and roof tiles, that could be shaken down by a major quake.

“Seventy million people in three dozen states are vulnerable to earthquake,” Khadivi said. “It’s a general problem.”

And for some reason, he decided to introduce the bed here.

And now . . .

Pasadena police will start a monthlong test of a new radar device--one that snaps pictures of the drivers and license plates of vehicles exceeding the speed limit--on Nov. 2, and could put it in regular use as early as January.

And that could keep the city’s traffic court rather busy.

The machine, which underwent a one-day tryout in Pasadena in September, can cite up to 260 speeders an hour--quite a few more than the 10 or so that a police officer can handle in the same time. . . .

Los Angeles Rams regulars may be on strike, but the team’s cheerleaders are not. And they had a little extra job Tuesday at the Navy base in Long Beach Harbor, adding a special note of welcome for the crew of the U.S. missile frigate Crommelin when it arrived home once more--after six weeks in the Persian Gulf.

It was reported incorrectly here Oct. 8 that a Mojave man, convicted of burning a cross outside the Lancaster home of an interracial couple, had argued in his defense that the act was a joke. There was no such testimony at the trial or sentencing of Larry Mettert, 46, a Ku Klux Klan member also convicted of brandishing a deadly weapon, false imprisonment and two counts of civil disturbance in connection with other racial incidents in Lancaster. Mettert was sentenced to two years in jail.