AlQa'dah 19, 1433, Oct 5, 2012, SPA -- Japanese stocks extended gains for the second day Friday, lifted by a weakened yen and overnight gains on Wall Street, dpa reported. The benchmark Nikkei 225 Stock Average gained 38.71 points, or 0.44 per cent, to end at 8,863.3 while the broader-based Topix index was up 1.75 points, or 0.24 per cent, at 737.13. For the week, the Nikkei edged down 0.08 per cent and the Topix was down 0.04 per cent. The yen's fall against the euro helped support some exporters. A weaker yen makes Japanese products less expensive overseas and improves repatriated revenues. Shares in Sony Corp surged 2.82 per cent, construction machinery maker Komatsu Ltd gained 2.18 per cent, Panasonic Corp jumped 1.58 per cent and Ricoh Co was up 0.55 per cent. The Bank of Japan decided Friday to refrain from additional monetary easing despite growing political pressure for it to help prop up the world's third-largest economy. The bank said in mid-September it would expand an asset-purchase programme to about 80 trillion yen (1.02 trillion dollars) from 70 trillion yen. The Dow Jones Industrial Average added 0.6 per cent Thursday in reaction to positive US employment data and a statement by the European Central Bank that it stands ready to buy the government bonds of struggling eurozone counties. On currency markets at 3 pm (0600 GMT) in Tokyo, the dollar traded at 78.39-45 yen, down from Thursday's 5 pm quote of 78.60-61 yen. The euro was quoted at 101.97-98 yen, up from 101.76-78 yen late Thursday, and at 1.3005-3007 dollars, up from 1.2947-2948 dollars.