It’s a Roller-Coaster Ride for Disk-Drive Maker Micropolis : Technology: Earnings have gone from a net income of $15 million in first nine months of 1992 to a net loss of $14 million during the same period this year.

No wonder Wall Street has a fickle attitude toward high-technology stocks.

Consider Micropolis Corp., a Chatsworth company that makes computer disk drives, the devices inside computers that record, store and retrieve information.

In the past 12 years, the firm’s earnings have reversed direction--going from good to bad and back to good again--seven times, according to Value Line, a New York-based investment research firm.

Lately Micropolis and other disk-drive makers have been on another downswing, primarily because of an industry-wide price war that broke out last spring.

After posting a $13-million, third-quarter net loss last week--compared with a $7-million profit a year ago--Micropolis said it expected more red ink before earnings improved, possibly in the first quarter of 1994. For its fiscal third quarter that ended Sept. 24, its revenue declined 12% to $91 million.

For the nine months, Micropolis posted a $14-million net loss on $293 million of sales, contrasted with net income of $15 million on sales of $305 million for the first nine months of 1992.

This wild roller coaster ride of boom and bust has played havoc with the company’s stock price. Its shares, down 60% from a peak of $16 in mid-1991, closed Monday at $6.50 in Nasdaq composite trading.

A relatively small player in the $24-billion disk-drive industry, Micropolis makes powerful disk drives used in high-end personal computers and workstations. Such drives, capable of storing more than one gigabyte of data--equal to about one billion characters--are the fastest-growing segment of the market.

Micropolis faces only a handful of other companies in this market, but they include some of the biggest names in the computer business: Seagate Technology of Scotts Valley, IBM, Hewlett-Packard Corp. and Conner Peripherals Inc. in San Jose.

Analysts say these high-capacity disk drives are the most likely to benefit from the interactive-video revolution, which got a large boost last week from Bell Atlantic Corp.’s bid to acquire cable giant Tele-Communications Inc.

Such technology, delivering entertainment and a wide array of services into the home via phone or cable lines, will require computers capable of storing massive quantities of data.

“A normal two-hour movie, digitized so it can be delivered into the home, will chew up maybe three or four gigabytes of storage--a tremendous amount,” said Robert Rodriguez, chief investment officer of the $152-million First Pacific Advisers Capital stock mutual fund in Los Angeles, and one of Micropolis’ largest shareholders.

The loss in the latest quarter included a $5.5-million charge related to layoffs at the company last month, when it let go 205 people, or about 14% of its work force. Micropolis also lost one of its biggest customers, computer-maker Digital Equipment Corp. of Maynard, Mass., which has begun producing and selling its own high-end disk drives.

The recent price war has hit Micropolis especially hard, because the company’s larger rivals produce more disk drives, and their per-unit cost is less.

In the disk-drive business, product prices normally decline 3% to 5% a quarter as one product generation ages and another comes along. Earlier this year, “the rate of decline was more like 20% a quarter,” said Rodriguez. “It slowed to 10% in the third quarter and now seems to be stabilizing closer to the normal rate.”

Since it is tough for Micropolis to compete on price, there is pressure on the firm “to be first in the market with bigger and faster drives and to keep looking for customers willing to pay more for them,” said Michael Murphy, editor of California Technology Stock Letter in Half Moon Bay, Calif.

“It’s not a bad philosophy,” he added. “It’s worked for them before and I think it will work again.”

Micropolis has some new products coming next year that analysts say look promising. They include so-called disk-array systems, which provide relatively inexpensive data storage for computer networks.