Anybody doing this - if so would like to know what you are using. Interested in any solutions just for US markets but really want to scan as many symbols as possible across global markets. Delayed data is OK but must be streaming, not EoD download solution. Previously have been using TS2000i and Hyperserver for Yahoo which will run around 4,000 symbols. Yet to trial it, but the latest Multicharts seems to offer a way to scan thousands of stocks from e.g. eSignal - beyond the 2500 max symbol limit maybe. Really need to keep to a retail price point and standard software ( I am not an SDK programmer). Maybe MC is my solution but there could be something right under my nose that others are using but I don't know about - hence this post.
Depending on what you are scanning for, and what your ' retail price' is. Maybe you could look at Xenith from Reuters with Metastock. http://www.metastock.com/products/realtime/xenith/?overview They can offer delayed data and live data subject to paying exchange fees You would have to ask them the exact details for what you are trying to do.
Data from 50 exchanges from yahoo/mldownloader http://www.trading-tools.com/mld.htm or from www.eoddata.com use metastock or multicharts to scan.
Yahoo data is often problematic. Take a look at SPY historical data from the past few days. It can take yahoo weeks to fix that. A reliable vendor is a better choice. Free comes at the expense of reliability. As far as scanning it depends for what. If you are going to scan for .some crossovers or MACD signals then with a universe of 10,000 you will get many signals. How do you know they are not random signals? TC2000 gets the signals fast but no analysis to reject randomness. What about if by chance you get 20 random signals in a row?