much noise comes from and iMac from the USB cables, beads will greatly reduce the noise... Fred
On 6/5/16 9:35 AM, John wrote: > Can’t do that - with the iMac the power supply is built in…it’s an > all-in-one. > > > > > On 5 Jun 2016, at 2:42 PM, Buck via Elecraft <elecraft@mailman.qth.net> wrote: > > Here is the authority on the issue. http://audiosystemsgroup.com/RFI-Ham.pdf > > Have you put ferrite on the cables from the iMac and the switching power > supply? > > You've used "star" grounding around the KX3. Try bonding everything to > everything - you want to provide a low-impedance parallel path from case to > case everywhere there is a connection. So, there should be a bond between the > soundcard and the iMac and the soundcard and power supply. Also the iMac > and soundcard to the PX3. Your diagram should look more like a spider web. > > Are the interconnecting cables grounded to the chassis or the circuit board? > You'll have to open some things up and see if there is the "pin 1 problem" > where the cable's ground is on the circuit board and not the chassis. > > I would look for a YouTube video on how to open up that iMac. I am sure > someone has posted one. > > K4ia > Buck > Honor Roll 335 > 8BDXCC > > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to f...@fmeco.com -- Fred Moore email: f...@fmeco.com f...@safes.com phone: 321-217-8699 ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
