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
kg9hfrank@gmail.com
> On Nov 26, 2019, at 7:41 AM, Artek Manuals <Manuals@ArtekManuals.com> 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
> Manuals@ArtekManuals.com
> www.ArtekManuals.com
>
>
> _________________
> Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
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