dear sir, i hava something to ask you... how to make used the knob? after i type the source code in textpad and it manage to compiled it.. but the knob is not function.....do we need to rewrite another source code for each knob? can you please send me the knob.java file if we need it to make it available to use by user.... by the way, i found that from your website about the oscilloscope, after we drag the knob...then the second time when we return to the page...the knob can't be used already....it is not function...? why this happen? thanks for help!