Hello Thank you for your sugestion. adding low pass filter into the USB DC line, it is enable to control with audio thru one USB cable. I will try and report.
best 73 JA7TDO Alberto I2PHD ????????: > > > Miura Kazunori wrote: > > Hello, Adnan > > > > I have same problem of thinking schematics. > > I am making SDR with USB control. > > A noise arrive through a USB cable. > > I think that it is necessary to insulate a PC and SDR. > > But I do not yet understand the method. > > Does anyone have idea? > > > > JA7TDO > > Kazunori Miura > > I had a similar problem when interfacing the SDR-X (an SDR radio that > did not enter into the market) to the PC via the > parallel port. A lot of noise entered the SDR through the parallel > cable. The solution was that of using opto-couplers > so that to not have an electrical path between the two equipments. Maybe > something similar could be designed for the USB > port > > 73 Alberto I2PHD > >
