A whistle blower went to his reward yesterday.

The reward - shades of 1950s television - was an anonymous, tax-free cashier's check for $10,000, disbursed by prearranged rendezvous in a downtown Washington hotel suite.

The whistle-blower was Dale M. Kuehn (rhymes with "clean"), a 30-year-old former auditor with the Federal Energy Administration. Kuehn said he had been asked to resign last August - and did so - after accusing his FEA superiors of supressing an investigation into shady practices involving the delivery of oil and natural gas to a Florida utility.

Kuehn's charges resulted in a series of articles in The St. Petersburg (Fla.) Times, plus a segment on CBS's "60 Minutes," documenting a system of kickbacks and fraudulent middleman charges that had added as much as $8.5 million to the price Florida consumers were paying for electricity.

The anonymous benefactor learned of Kuehn's activities by watching "60 Minutes," according to Harry S. Ashmore, a former Pulitzer-Prize-winning newspaperman who delivered the check yesterday.

"He's a very unconventional guy," said Ashmore of the donor, whom he identified only as the head of a small family foundation in California. "I have known him well for 20 years . . . He likes to make these gifts after the fact without any publicity.

"I really have the feeling sometimes that he is playing 'The Millionaire,'" said Ashmore, referring to the television series in which lawyer "Michael Anthony" dispensed $1 million cashier's checks on behalf of a philanthropist called "John Beresford Tiption," who was never seen.

Ashmore, now with the Center for the Study of Democratic Institutions in Santa Barbara, Calif., said he had been asked to conduct a small investigation to verify the deserving nature of Kuehn's actions, and had in the past conducted several similar investigations for the same client.

But he said he could not promise that there would be more such gifts in the future. "I don't think he wants to get into this as a business," said Ashmore.

When Ashmore reported back that he was satisfied, the benefactor "handed me a certified check for $10,000 and said woudl you deliver this to Mr. Kuehn." Ashmore notified Kuehn by telephone last Saturday, and they arranged to meet at the Hotel Jefferson yesterday afternoon.

Kuehn, a former army paratrooper in Vietnam, said the gift was a "great surprise," with which he plans to finance his further training as an accountant.

"I have no intention of trying to use it in a frivolous manner," said Kuehn. "I would like to do something in the future in the public interest. I would certainly consider working in the government." But the normal fate of a whistle-blower, he added, is to be "blacklisted."

Kuehn went to work for the FEA in the fall of 1976, at an annual salary of $8,500, and in March 1977 he was given responsibility for overseeing an audit of some suspect oil transactions.

"I had great responsibility and absolutely no authority," said Kuehn. "The reason that I was given this job was that FEA in Houston had absolutely no desire to do anything with this case.

"I had no experience," Kuehn acknowledged. "It was widely believed that I could be handled. It was probably widely believed that I was none too bright."

After his resignation, Kuehn went to a reorter at The St. petersburg Times, which soon revealed that the chairman of the Florida Power Col had received $193.255 in "fingers's fees" from a Florida fuel consultant. The Times subsequently described a chain of intermediary companies adding charges onto the cost of fuel and, ultimately, electricity.

Similar patterns of alleged overcharges were later uncovered by The St. Petersburg Times uncovered in Chicago and Pittsburgh.

Although an FEA internal investigation has since cleared Kuehn's supervisors, according to The Times a grand jury is currently looking into possible criminal conspiracy charges.

"My understanding," said Ashmore as the two men posed for pictures, each grasping one end of the check. "is that this is a tax exempt gift. I don't think you have to report it." Ashmore said, however, that the donor had agreed to provide the Internal Revenue Service with any documentation they might request when Kuehn files his 1978 tax return.

"If you had any income, this check would of course be much more valuable," Ashmore added. CAPTION: Picture, Dale M. Kuehn, who was asked to resign for whistle blowing at the FEA, shows off his $10,000 reward. By Margaret Thomas - The Washington Post