Hi T-Learner
Actually this post should have been in the "Technical Analysis " section. You already know that the ascending triangles are for "Buy" and reverse of this is for "sell".
Anyway the basics are as follows...
When the price forms two or more peaks of equal height and two or more higher troughs (lows) then the pattern formed is called ascending triangles. The equal peaks form a horizontal line. The trend line drawn through the rising troughs is an ascending trend line, which will converge towards the horizontal line. This pattern is formed when the price moves up and it becomes overbought. The selling, which emerges pulls down the price. However buying resurfaces and takes the price up again. The price is unable to break the previous resistance (recent high) and is pulled down again. But buying emerges at a higher level than before and takes the price higher again. Most recent one I came across is of BILT. Chart enclosed for reference.
Ascending triangle is very easy to spot. They are considered bullish patterns are very reliable when found in an up trend.
At some point the price breaks the resistance and is propelled to much higher levels on renewed buying interest. In other word the price breaks out of the ascending triangle and moves upwards. Also note that normally the volume contracts during the ascending triangle pattern and when the breakout happens volume increases. The volume increase is considered as a confirmation of breakout. You can have a look at the price breaking out the ascending triangle and the corresponding increase in volume in the enclosed chart of BILT. The concept of breakout has been discussed extensively in a separate thread with excellent posts by Amit, Saint and Ajay. Please refer this tread for more details.
http://www.traderji.com/showthread.php?t=3392
So ascending triangle present good buying opportunities during the breakout. So one has to look for the breakout with good increase in volume. The price should close higher than the resistance line (top horizontal line) with increased volumes.
The reverse of the ascending triangles is the descending triangles, which are bearish patterns that breakout out in the down side. These can be noticed by their horizontal support lines and descending trend line at the top.
Regards
karthik