6.4% Earnings Drop in Second Quarter Reported by AT

American Telephone & Telegraph Co. today reported its second-quarter earnings fell 6.4% due to lower equipment sales and unexpectedly high start-up costs for the company’s new credit card.

AT&T; said it earned $657 million, or 60 cents a share, in the quarter ended June 30, down from $699 million, or 65 cents a share, in the same quarter of 1989.

Revenue also fell, to $9.03 billion from $9.26 billion in the same quarter of last year.

The company said the disappointing results were due mostly to slower sales of corporate telephone systems, data communications gear and equipment sold to the federal government, as well as unexpectedly high costs for processing applications for its Universal card, which combines a MasterCard or Visa with telephone charging privileges.