Topband: Computer noise

[fmoeves]

One more I forgot. I have 2 bikes and I have battery tenders on them. These things make lots of noise all the way up to 40m.Battery Tender is the brand. I put timers on them so they operate when I'm not. Fred KB4QZH 
-------- Original message --------From: fmoeves <fmoeves at twc.com> Date: 11/26/19  9:26 AM  (GMT-05:00) To: topband at contesting.com Subject: Re: Topband: Computer noise Don't forget lights. I just installed 2 8' 4 bulb t8 lights from Home Depot. Terrible rfi on 160 Cooper lighting sent me new ones with filters in them worked great. HD sell commercial lights with no filters. I also have chokes on everything that enters my PC. And have started using the big 4" and 2.5 chokes with rg-400 at antenna feed points. Really cut down on rfi, noise and PC lockups. Fred KB4QZH -------- Original message --------From: Artek Manuals <Manuals at ArtekManuals.com> Date: 11/26/19  8:41 AM  (GMT-05:00) To: topband at contesting.com Subject: Re: Topband: Computer noise Could be coming from the power supply? Sometimes simple clip on chokes are not enough either. I have a similar problem here on 20M I have dual (Identical) monitors . One has an irritating but not debilitating  spur on 20 the other doesn't ..If I swap the monitors the spur follows the monitor. Have tried a handful of ferrites to no avail so it is likely "radiated" IMO  and not conducted.Grumpy DaveNR1DXOn 11/26/2019 6:41 AM, Rodman, David wrote:> A few ideas might be helpful here.  I was at the station over the weekend and found a significant amount of noise coming from one of two computers in the station.  Significant noise S5 at 1820.  One computer runs the cluster and 2m connection.  That was clean.  The other handles most of the remote chores and has about 15 USB serial devices attached.  Everything was off, except a battery operated transceiver attached to the receive antenna feed, the modem for the cable and my router.  One can definitely see that operating the computer, closing windows or plugging in USB devices causes the modulation on the signal to change, this isolating the source to the computer alone and possible connections to peripherals (they were all turned off by the way).  I did have few chokes available but attaching them to the USB wires out of the computer to their various devices made no improvement.  I could get more specific but need to leave for my office now.  Any ideas might be helpful and appreciat>   ed.>>> ---> David J Rodman MD> Assistant Clinical Professor> Department of Ophthalmology> SUNY/Buffalo>> Office 716-857-8654> _________________> Searchable Archives: http://www.contesting.com/_topband - Topband Reflector-- DaveManuals at ArtekManuals.comwww.ArtekManuals.com_________________Searchable Archives: http://www.contesting.com/_topband - Topband Reflector_________________Searchable Archives: http://www.contesting.com/_topband - Topband Reflector