This question is for all experimented electronics workers, hobbysts, designers, etc. I am interested in to buy a cheap but broad range oscilloscope but I don't know what parameters must I pay attention. I have seen 2 kind of oscilloscopes and I don't know which is the best choice. 1)A handheld oscilloscope with LCD display,RS232 interface,like Oszifox 2)A classical oscilloscope like Instek GOS-310 10MHz OTOH, I have been studying some projects and one of them names a double beam scope, are double beam the 2 choices. I have basic electronics and repairing knowledge, and I am constantly study from tutorials or good books like the Lessons by Kuphaldt, because my wish is to be a practical designer. I want to use the scope for: learning the working of all circuits (analogs and digitals), repairing TV,PC Monitors,(i.e. Measuring the chroma RGB signals,the H/V sync signals,the H/V outputs, the antenna signal,etc), RF Circuits, Stereo, etc. I thank your help.