Hi!
I just moved to an apartment and wanted to keep my radio in the bathroom, same as I did in the last place I lived.
Only problem with this place is that the main electrical drop to the building is right outside my bathroom wall, interfering with FM/AM reception.
Is there anything I can do to alleviate this - putting a noise filter on the radio power cord, etc??
Right at the frequency of an AM I've been listening to for years, is a loud combination buzz/screeching sound.
Chris K-Man wrote:_______
Hi!
I just moved to an apartment and wanted to keep my radio in the bathroom, same as I did in the last place I lived.
Only problem with this place is that the main electrical drop to the building is right outside my bathroom wall, interfering with FM/AM reception.
Is there anything I can do to alleviate this - putting a noise filter on the radio power cord, etc??
Right at the frequency of an AM I've been listening to for years, is a loud combination buzz/screeching sound.
Maybe a variable-frequency drive for an induction motor in some HVAC
blower. Those things are super bad news. Or it might just be a whole
building full of SMPSes.
Cheers
Phil Hobbs
--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510
http://electrooptical.net
http://hobbs-eo.com
Chris K-Man wrote:_______
On Tuesday, July 19, 2022 at 4:08:33 PM UTC-4, Phil Hobbs wrote:
Chris K-Man wrote:It happens only to radios brought into this bathroom. Lots of static on FM, intermittent
Hi!Maybe a variable-frequency drive for an induction motor in some HVAC
I just moved to an apartment and wanted to keep my radio in the bathroom, same as I did in the last place I lived.
Only problem with this place is that the main electrical drop to the building is right outside my bathroom wall, interfering with FM/AM reception.
Is there anything I can do to alleviate this - putting a noise filter on the radio power cord, etc??
Right at the frequency of an AM I've been listening to for years, is a loud combination buzz/screeching sound.
blower. Those things are super bad news. Or it might just be a whole
building full of SMPSes.
multiplex(stereo for the young uns!) and loud static and that buzzy-shriek right below
80 on the standard dial(AM).
Once the boombox is moved somewhere else in the apt, it performs like a normal set.
This is (an example of) what I can see in the upper LH corner of my bathroom window:
https://i.pinimg.com/originals/2e/3c/ce/2e3cceb1c024f799276a55ab05b44240.png
A big honkin one, twice the size of a residential service! And the closer a radio set gets
to that thing, the worse it buzzes
Well, there's more loop area there to spray magnetic fields around than
there is in the cables in the wall. The nasty high-frequency currents
are probably coming from VFDs, switching supplies, and so on.
I build a lot of sensitive front end amps in instruments, so I feel your pain. You still hear people advocating for star grounds, split ground
planes, and so on. Those were great in 1950, but in 2022 there's so
much RF and miscellaneous hash running round that a split ground plane
is as good as an antenna.(*)
Cheers
Phil Hobbs
(*) There are fairly popular antenna designs based on slots and patches
in planar conductors.
On Tuesday, July 19, 2022 at 4:08:33 PM UTC-4, Phil Hobbs wrote:
Chris K-Man wrote:
Hi!Maybe a variable-frequency drive for an induction motor in some HVAC
I just moved to an apartment and wanted to keep my radio in the bathroom, same as I did in the last place I lived.
Only problem with this place is that the main electrical drop to the building is right outside my bathroom wall, interfering with FM/AM reception.
Is there anything I can do to alleviate this - putting a noise filter on the radio power cord, etc??
Right at the frequency of an AM I've been listening to for years, is a loud combination buzz/screeching sound.
blower. Those things are super bad news. Or it might just be a whole
building full of SMPSes.
It happens only to radios brought into this bathroom. Lots of static on FM, intermittent
multiplex(stereo for the young uns!) and loud static and that buzzy-shriek right below
80 on the standard dial(AM).
Once the boombox is moved somewhere else in the apt, it performs like a normal set.
This is (an example of) what I can see in the upper LH corner of my bathroom window:
https://i.pinimg.com/originals/2e/3c/ce/2e3cceb1c024f799276a55ab05b44240.png
A big honkin one, twice the size of a residential service! And the closer a radio set gets
to that thing, the worse it buzzes
Chris K-Man wrote:______________
On Tuesday, July 19, 2022 at 4:08:33 PM UTC-4, Phil Hobbs wrote:
Chris K-Man wrote:It happens only to radios brought into this bathroom. Lots of static on FM, intermittent
Hi!Maybe a variable-frequency drive for an induction motor in some HVAC
I just moved to an apartment and wanted to keep my radio in the bathroom, same as I did in the last place I lived.
Only problem with this place is that the main electrical drop to the building is right outside my bathroom wall, interfering with FM/AM reception.
Is there anything I can do to alleviate this - putting a noise filter on the radio power cord, etc??
Right at the frequency of an AM I've been listening to for years, is a loud combination buzz/screeching sound.
blower. Those things are super bad news. Or it might just be a whole
building full of SMPSes.
multiplex(stereo for the young uns!) and loud static and that buzzy-shriek right below
80 on the standard dial(AM).
Once the boombox is moved somewhere else in the apt, it performs like a normal set.
This is (an example of) what I can see in the upper LH corner of my bathroom window:
https://i.pinimg.com/originals/2e/3c/ce/2e3cceb1c024f799276a55ab05b44240.png
A big honkin one, twice the size of a residential service! And the closer a radio set gets
to that thing, the worse it buzzes
Well, there's more loop area there to spray magnetic fields around than
there is in the cables in the wall. The nasty high-frequency currents
are probably coming from VFDs, switching supplies, and so on.
I build a lot of sensitive front end amps in instruments, so I feel your pain. You still hear people advocating for star grounds, split ground
planes, and so on. Those were great in 1950, but in 2022 there's so
much RF and miscellaneous hash running round that a split ground plane
is as good as an antenna.(*)
Cheers
Phil Hobbs
(*) There are fairly popular antenna designs based on slots and patches
in planar conductors.
On Tuesday, July 19, 2022 at 4:08:33 PM UTC-4, Phil Hobbs wrote:
Chris K-Man wrote:
Hi!
I just moved to an apartment and wanted to keep my radio in the bathroom, same as I did in the last place I lived.
Only problem with this place is that the main electrical drop to the building is right outside my bathroom wall, interfering with FM/AM reception.
Is there anything I can do to alleviate this - putting a noise filter on the radio power cord, etc??
Right at the frequency of an AM I've been listening to for years, is a loud combination buzz/screeching sound.
Maybe a variable-frequency drive for an induction motor in some HVAC blower. Those things are super bad news. Or it might just be a whole building full of SMPSes.
Cheers
Phil Hobbs
--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510
http://electrooptical.net_______
http://hobbs-eo.com
It happens only to radios brought into this bathroom. Lots of static on FM, intermittent
multiplex(stereo for the young uns!) and loud static and that buzzy-shriek right below
80 on the standard dial(AM).
Once the boombox is moved somewhere else in the apt, it performs like a normal set.
This is (an example of) what I can see in the upper LH corner of my bathroom window:
https://i.pinimg.com/originals/2e/3c/ce/2e3cceb1c024f799276a55ab05b44240.png
A big honkin one, twice the size of a residential service! And the closer a radio set gets
to that thing, the worse it buzzes
On Tuesday, July 19, 2022 at 5:28:18 PM UTC-4, Phil Hobbs wrote:
Chris K-Man wrote:_______
On Tuesday, July 19, 2022 at 4:08:33 PM UTC-4, Phil Hobbs wrote:Well, there's more loop area there to spray magnetic fields around than
Chris K-Man wrote:It happens only to radios brought into this bathroom. Lots of static on FM, intermittent
Hi!Maybe a variable-frequency drive for an induction motor in some HVAC
I just moved to an apartment and wanted to keep my radio in the bathroom, same as I did in the last place I lived.
Only problem with this place is that the main electrical drop to the building is right outside my bathroom wall, interfering with FM/AM reception.
Is there anything I can do to alleviate this - putting a noise filter on the radio power cord, etc??
Right at the frequency of an AM I've been listening to for years, is a loud combination buzz/screeching sound.
blower. Those things are super bad news. Or it might just be a whole
building full of SMPSes.
multiplex(stereo for the young uns!) and loud static and that buzzy-shriek right below
80 on the standard dial(AM).
Once the boombox is moved somewhere else in the apt, it performs like a normal set.
This is (an example of) what I can see in the upper LH corner of my bathroom window:
https://i.pinimg.com/originals/2e/3c/ce/2e3cceb1c024f799276a55ab05b44240.png
A big honkin one, twice the size of a residential service! And the closer a radio set gets
to that thing, the worse it buzzes
there is in the cables in the wall. The nasty high-frequency currents
are probably coming from VFDs, switching supplies, and so on.
I build a lot of sensitive front end amps in instruments, so I feel your
pain. You still hear people advocating for star grounds, split ground
planes, and so on. Those were great in 1950, but in 2022 there's so
much RF and miscellaneous hash running round that a split ground plane
is as good as an antenna.(*)
Cheers
Phil Hobbs
(*) There are fairly popular antenna designs based on slots and patches
in planar conductors.
Should an electrical service mast like the one I linked to cause that level of EMI?
Should an electrical service mast like the one I linked to cause that level of EMI?
In article <f3c1f08b-2a62-4f7a...@googlegroups.com>,____________________
Chris K-Man <thekma...@gmail.com> wrote:
Should an electrical service mast like the one I linked to cause that level of EMI?By itself, no. It ought to be a fairly passive pass-through for AC
current, with no mechanism for generating RFI. If there's a loose wire
or other bad connection, it could be making noise (and possibly overheating and creating a safety hazard).
Seems to me there are two possible sources of the RFI you are suffering:
(1) Industrial equipment on that line (welders, big brush motors,
switching power supplies) which are generating RFI internally and
feeding it back into the mains. Here in the US, "Class A" equipment
(for use in business environments) is allowed a lot more RFI leakage
than "Class B" (residential), and industrial equipment is even worse.
(2) A physical fault in the mains wiring, which is causing arcing and sparking, corona discharge, and so forth. Two fairly common problems
on power distribution poles are bad insulators (with electricity
arcing over them) and loose or defective ground connections. Arcing
in a circuit-breaker panel (e.g. a breaker going bad) could have
a similar effect.
In both cases the noise can travel quite a long distance along power
wiring to the point where it troubles you.
There are a few ways that can be used to track the location of a noise
source or fault of this type. Corona discharges and arcs often
generate a lot of ultrasonic noise, and there are ultrasound receivers
with directional microphones which shift this noise down into the
audible band. Arcing and corona can also generate noise up into the
VHF band which can be tracked using a receiver and a directional
antenna (e.g. a small hand-held Yagi). A spectrum analyzer hooked to
a directional antenna can be a useful tool as you may be able to see
specific noise lines bouncing up and down.
And I understand that the head of the service mast - the part visible above and
to the left of the bathroom window, is only part of the package. I will take outside
a small portable radio, and walk around within 8 feet of the meters at the base of
the service mast, and see what happens at the frequency of the AM station I listen
to.
On Tuesday, July 19, 2022 at 5:28:18 PM UTC-4, Phil Hobbs wrote:
Chris K-Man wrote:
On Tuesday, July 19, 2022 at 4:08:33 PM UTC-4, Phil Hobbs wrote:Well, there's more loop area there to spray magnetic fields around than
Chris K-Man wrote:It happens only to radios brought into this bathroom. Lots of static on FM, intermittent
Hi!Maybe a variable-frequency drive for an induction motor in some HVAC
I just moved to an apartment and wanted to keep my radio in the bathroom, same as I did in the last place I lived.
Only problem with this place is that the main electrical drop to the building is right outside my bathroom wall, interfering with FM/AM reception.
Is there anything I can do to alleviate this - putting a noise filter on the radio power cord, etc??
Right at the frequency of an AM I've been listening to for years, is a loud combination buzz/screeching sound.
blower. Those things are super bad news. Or it might just be a whole
building full of SMPSes.
multiplex(stereo for the young uns!) and loud static and that buzzy-shriek right below
80 on the standard dial(AM).
Once the boombox is moved somewhere else in the apt, it performs like a normal set.
This is (an example of) what I can see in the upper LH corner of my bathroom window:
https://i.pinimg.com/originals/2e/3c/ce/2e3cceb1c024f799276a55ab05b44240.png
A big honkin one, twice the size of a residential service! And the closer a radio set gets
to that thing, the worse it buzzes
there is in the cables in the wall. The nasty high-frequency currents
are probably coming from VFDs, switching supplies, and so on.
I build a lot of sensitive front end amps in instruments, so I feel your
pain. You still hear people advocating for star grounds, split ground
planes, and so on. Those were great in 1950, but in 2022 there's so
much RF and miscellaneous hash running round that a split ground plane
is as good as an antenna.(*)
(*) There are fairly popular antenna designs based on slots and patches______________
in planar conductors.
The point is, it's an issue, especially at certain parts of the AM dial, when a radio
is within 10 feet of the service mast outside my bathroom corner window. Outside
of the bathroom corner of the apt, the interference drops off exponentially.
On Tuesday, July 19, 2022 at 4:08:33 PM UTC-4, Phil Hobbs wrote:
Chris K-Man wrote:_______
Hi!Maybe a variable-frequency drive for an induction motor in some HVAC
I just moved to an apartment and wanted to keep my radio in the bathroom, same as I did in the last place I lived.
Only problem with this place is that the main electrical drop to the building is right outside my bathroom wall, interfering with FM/AM reception.
Is there anything I can do to alleviate this - putting a noise filter on the radio power cord, etc??
Right at the frequency of an AM I've been listening to for years, is a loud combination buzz/screeching sound.
blower. Those things are super bad news. Or it might just be a whole
building full of SMPSes.
Cheers
Phil Hobbs
--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510
http://electrooptical.net
http://hobbs-eo.com
It happens only to radios brought into this bathroom. Lots of static on FM, intermittent
multiplex(stereo for the young uns!) and loud static and that buzzy-shriek right below
80 on the standard dial(AM).
Once the boombox is moved somewhere else in the apt, it performs like a normal set.
This is (an example of) what I can see in the upper LH corner of my bathroom window:
https://i.pinimg.com/originals/2e/3c/ce/2e3cceb1c024f799276a55ab05b44240.png
A big honkin one, twice the size of a residential service! And the closer a radio set gets
to that thing, the worse it buzzes
Hi!
I just moved to an apartment and wanted to keep my radio in the bathroom, same as I did in the last place I lived.
Only problem with this place is that the main electrical drop to the building is right outside my bathroom wall, interfering with FM/AM reception.
Hi!
I just moved to an apartment and wanted to keep my radio in the bathroom, same as I did in the last place I lived.
Only problem with this place is that the main electrical drop to the building is right outside my bathroom wall, interfering with FM/AM reception.
Is there anything I can do to alleviate this - putting a noise filter on the radio power cord, etc??
Right at the frequency of an AM I've been listening to for years, is a loud combination buzz/screeching sound.
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