* U.S. payrolls show unexpected drop in September
* Dollar falls below 82 yen to 15-year low
* Fed's Bullard earlier says more easing not obvious case (Updates prices, adds technical details on euro/dollar)
By Gertrude Chavez-Dreyfuss
NEW YORK, Oct 8 (Reuters) - The dollar slumped to a 15-year low against the yen on Friday after data showed an unexpected drop in U.S. payrolls in September, bolstering expectations of further easing by the Federal Reserve to revive a sputtering economy.
That should ensure the dollar's weak trend remains intact as the Fed's quantitative easing measures involve asset purchases meant to push long-term yields lower.
Traders are now focusing on the 80-yen level for the dollar after it fell to a low of 81.72 yen following the employment report, which showed 95,000 job cuts last month.
The dollar also fell sharply against the euro on the jobs data, but it later recovered after Eurogroup Chairman Jean-Claude Juncker said he was not happy with the euro's move to $1.4000, a level surpassed on Thursday.
On the week, the euro was up 0.9 percent, its fourth straight week of gains.
"The impact of the (jobs) report was negative for the dollar, as it increased the likelihood of further QE measures later this year," said Michael Woolfolk, senior currency strategist at BNY Mellon, in New York.
"The U.S. is struggling to bring its unemployment rate down as heightened uncertainty and a lack of credit growth undermine business sentiment and discourage new hiring," he added.
In late afternoon trading, the dollar was at 82.16 yen, down 0.3 percent on the day, according to electronic trading platform EBS. Investors remained on full alert for intervention by the Bank of Japan to weaken the yen as it is trading at levels stronger than the 82.87 level where the Japanese central bank stepped in on Sept 15.
Japan Prime Minister Naoto Kan said Tokyo would take decisive steps on the strong yen if needed, but added that it also wanted to cooperate with the Group of Seven industrialized countries and others.
EURO FALL
Investors are also wary in case the G7 and International Monetary Fund meetings starting in Washington on Friday produce a surprise in the form of a coordinated front on currencies, as calls have mounted for global efforts to avoid competitive currency devaluations.
The euro last traded little changed against the dollar at $1.3928, paring gains after Juncker said on Friday the euro is too strong against the dollar at $1.40. He made the comment ahead of the meeting of finance ministers and central bankers of the G7.
"Juncker's comments were the clearest indication yet that euro zone officials are growing uncomfortable with the single currency's export-sapping strength," said Omer Esiner, chief market analyst at Commonwealth Foreign Exchange in Washington.
"The greenback stands to benefit further if euro zone monetary officials begin to take a more vocal stance against euro appreciation," Esiner said.
On technical charts, the euro failed to strengthen above $1.40 on Friday. Traders said the key figure to watch is the 38.2 percent retracement of Thursday's peak at $1.4030 and the low at $1.3857 and this comes in at $1.3923. If the euro stays below these levels, then the bias is tilted to the downside.
Also on Friday, St. Louis Fed chief James Bullard, a voting member this year on the Fed's rate-setting committee, told CNBC that U.S. policymakers face a tough decision at next month's policy meeting as the economy has slowed, but is still bumping along.
Market speculation has increased that the Fed will resume quantitative easing when it meets on Nov. 2-3 to shore up the economy. Bullard did not rule this out, saying more help may be needed to push up inflation.
The dollar index, a non-traded calculation of the dollar's performance against a basket of six other major currencies, was down 0.2 percent at 77.265, though above an 8-1/2-month low of 76.906 touched on Thursday. It has support at 76.60, the index low for 2010 hit in mid-January.