I have an HP laptop charger that sings like mad. Interestingly enough I have another identical one that is absolutely quiet. Inadvertently, I do forget about that and my noise level jumps up to S-9. Most times I remember the source LOL,
-73- Frank KG9H [email protected] > On Nov 26, 2019, at 7:41 AM, Artek Manuals <[email protected]> wrote: > > 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 Dave > NR1DX > > On 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 apprec iat >> 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 > > -- > Dave > [email protected] > www.ArtekManuals.com > > > _________________ > Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _________________ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
