> I recently discovered the source of a very annoying noise in my K3. When > unplugging the USB cable from my USB hub the noise in the receiver > disappears.
I had posted on this topic a couple weeks ago. I didn't discover my own noise problem until I was looking at the noise floor with a SDR-IQ and SpectraVue software. In my case, most of the noise from the USB-to-RS232 adapter is masked by band noise. I managed to wind 10-turns of the USB adapter cable through a 0.75-inch I.D. #31 ferrite core. The choke was placed as close as possible to the DB-9 connector. After winding, I detected no change which is unusual when using these cores. It may be that the noise is induced in differential mode between the USB adapter and the K3. I ended up discarding the adapter and went with a serial cable connected between the K3 and the one and only RS232 serial port on my PC. Problem solved. Paul, W9AC ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
