The key Indian equity indices opened on a flat note on Wednesday tracking a mixed trend in the Asian markets.The indices however, made marginal gains so far after opening on a flat note.At 9.36 a.m., the Sensex traded at 39,029.79 points, higher by 59.99 points or 0.15 per cent from the previous close of 38,969.80 points.It had opened at 39,086.21 and so far touched an intra-day high of 39,160.22 points and a low of 38,903.87 points.The Nifty50 on the National Stock Exchange traded at 11,720.10, higher by 11 points or 0.09 per cent from the previous close of 11,709.10 points.