Anything that that has volume can be charted. There are a large number of OTCBB issues that have extremely low or almost no trading at all. While it is technically correct that trading on a regular basis establishes a pattern...if that 'regular basis' is one 10k share trade a month, little useful TA will be available. However with an issue like ASTN, trading is more frequent and therefore certainly lends itself to TA. My experience has led me to a 100-300K per day minimum volume as a "floor" for reliable TA with the better results coming at the upper end of that scale. I have reviewed ASTN's charts and concur with your findings.