Don, Thanks for the quick response and I suspect you are correct. The shack here resembles more than one octopus - I've got my work cut out for me. I've read and saved many of Jim's excellent articles so I'll review them again and start there.
73, Mike On Tue, Dec 13, 2016 at 4:56 PM, Don Wilhelm <[email protected]> wrote: > Mike, > > That sounds like hum, buzz and noise being picked up by the connecting > cables. > > I would suggest that you follow Jim Brown's K9YC advice on bonding. > With heavy wire or braid, bond the various boxes following the path(s) of > the interconnecting cables and coax. The bonding will conduct that noise > onto the outside of the various enclosures instead of allowing the cable > shields to conduct that noise into the boxes and onto the ground plane. > > In days of old when connectors were mounted directly on the enclosure, > this sort of thing was not a problem - noise pickup on the cable shields > was conducted onto the outside of the enclosures and did not pose a problem. > In today's world, the shields of interconnecting cables are connected > directly to the ground plane inside the box containing the circuits (pin 1 > problem), and any noise picked up by the cable shield is transmitted to the > circuit ground plane. The bonding routes much of that noise onto the > outside of the enclosure and keeps it away from the circuits inside the box. > > 73, > Don W3FPR > > > On 12/13/2016 6:33 PM, Mike Murray wrote: > >> Since starting to use my K3/0 I've been bugged by a "buzz" coming from the >> speakers that I haven't been able to identify. Turning the volume up >> overrides the noise, but it's still there. I've tried 3 different power >> supplies with no change, including the one supplied by Elecraft. Here's a >> recording of what I'm hearing: >> >> ______________________________________________________________ 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 Message delivered to [email protected]
