[PLUG] Buzzing speakers - SOLVED!

Michael Barnes barnmichael at gmail.com
Thu Mar 26 03:43:40 UTC 2020


On Wed, Mar 25, 2020 at 2:22 PM Galen Seitz <galens at seitzassoc.com> wrote:

> On 3/25/20 9:17 AM, Michael Barnes wrote:
> > On Wed, Mar 25, 2020 at 8:51 AM Michael Barnes <barnmichael at gmail.com>
> > wrote:
> >>
> >> Model is VS-2121. The sound is not random. It happens at exactly :29 and
> >> :59. It is not quiet, either. We can hear it pretty much throughout the
> >> house, so it's not like something that has been there all along and just
> >> wasn't heard over ambient noise. It is more of a sound than noise, a low
> >> frequency rumble, but not like static type noise as you would get from
> AC
> >> hum or failing components. More like hitting the bottom note or bass
> pedal
> >> on a keyboard (musical keyboard, not computer keyboard). I'm not sure of
> >> whether it is coming from all speakers or just the sub-woofer, as I have
> >> not been at the computer when it happens. The computer is in my wife's
> >> hobby room. It is not used that much, only for email and occasional web
> >> surfing. Interesting that the on/off switch doesn't really turn it off.
> As
> >> I plug/unplug it, the subwoofer pops.
> >>
> >> Thanks for everyone's comments.
> >>
> >> Michael
> >>
> >> Well, it is not the computer. I turned the computer and monitor of and
> sat
> > there at the appointed time. It seems to be a power line issue. The sound
> > is coming from the subwoofer, although I had the speakers turned off.
> Next
> > chance I get to sit there at that time, I'll turn them on. I guess the
> next
> > thing is to see if it is only that breaker circuit. I have no idea what I
> > have in the house that would do something on the power precisely at those
> > times.
>
> Good idea to run a test with the computer turned off.  That's useful info.
>
> It certainly seems that power line noise is a potential culprit.  If you
> have a spare UPS sitting around, it would be interesting to see if the
> noise occurs when the speakers are powered by the UPS, but the UPS is
> unplugged from the wall, and the speakers are not connected to the
> computer.  I.e., turn your speakers into battery powered speakers that
> are isolated from line power and the computer, and listen to the results.
>
> What's interesting to me is that you indicated that this is a recent
> problem.  This suggests one of two possibilities:
>
> 1. A new, and very periodic noise source has been introduced into the
> speakers environment.
>
> 2. The noise source has always been there, but a component failure in
> the speakers has caused the noise to become noticeable.
>
> galen
> --
> Galen Seitz
> galens at seitzassoc.com


Source of problem discovered. Still working on why. My APRS base station
beacons every 30 minutes. For some reason, I recently started getting some
RFI into  things, this speaker being one of them. Just happened to be
looking at the APRS screen when it transmitted and heard the buzz at the
same time.  Now to figure out and solve why the RFI is only recently
getting into things.

Michael



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