On Jun 6, 2:45*pm, (Dave Platt) wrote:
I have been getting sounds in our house that seems to come from
electronic stuff around the house.
I also listened to what sounded like voices coming from behind the
computer?

Voices coming out of loudspeakers or other electronic equipment which
contains them, can occur as the result of strong radio frequency
signals. *A strong enough RF signal, modulated by someone's voice, can
be picked up by the household wiring (mains cables, telephone wire,
speaker cables, etc.) and leak into the electronic equipment. *Once
inside the equipment, it can be accidentally "detected" (converted
from radio frequencies back to audio) by semiconductors in the
circuitry, amplified, and played out through the equipment's speakers.

Telephones, answering machines, baby monitors, powered subwoofers,
computer speaker systems, etc. can all be prone to this. *I suppose
that an internal modem card in a PC - one with a loudspeaker - could
pick up enough RF via its phone-line connection to start detecting
audio in this way.

The strong RF signal might come from any of a number of sources... all
probably fairly close to the house. *Commercial AM transmitters can
cause this, as can ham-radio transmitters, and CB radios. *Here in the
U.S., *legal* CB transmissions usually aren't strong enough to cause
problems, but some CB operators use illegal high-power amplifiers that
can boost the signal far enough to cause this sort of inadvertent
pickup.

I don't know what the law is about this sort of problem in Canada.
Here in the U.S., the FCC generally considers it to be a defect in the
equipment which is picking up the RF - if a device isn't *supposed* to
be a radio, it shouldn't *behave" like a radio, is their thinking.
It's referred to as "undesired operation", and the "Part 15" notice
which comes with most consumer electronic devices says that the device
"must accept radio frequency interference, including that which causes
undesired operation."

There are several ways to address the problem:

- *Replace the RF-sensitive devices with better-designed devices that
* *don't have the problem.

- *Add RF filters or chokes to the phone lines, speaker cables, power
* *lines, etc. to block the RF before it enters the equipment.

- *Find the person or company whose transmitters are generating the RF,
* *and ask them to stop (they'll probably refuse, as they often have
* *a perfectly good legal license to transmit).

- *Live with it.

- *Move.

If you can find which pieces of equipment are picking up the RF (and,
in doing so, confirm that this is the problem) you can likely correct
the problem with some clamp-on ferrite chokes, and/or a telephone-line
RF filter (a DSL mini-filter may well do the job).

Seehttp://www.palomar-engineers.com/RFI_Kit/rfi_kit.htmlfor a kit of
ferrite components specifically intended for this sort of household
problem.

I'm not sure what connection there might be between the voices/noises
you are hearing, and any "voice over IP provider". *Your message isn't
clear whether you actually have telephone service over IP, or whether
you think someone else's voice-over-IP service is affecting you
accidentally (very unlikely, in my opinion).

--
Dave Platt * * * * * * * * * * * * * * * * * AE6EO
Friends of Jade Warrior home page: *http://www.radagast.org/jade-warrior
* I do _not_ wish to receive unsolicited commercial email, and I will
* * *boycott any company which has the gall to send me such ads!

Agree with all of that. Even 'back when' stories abounded about people
picking up radio transmissions on all kinds of unlikely devices; one
was about a lady who 'received' faint radio signals radio on her
electric heater. The outcome was that a corroded connection was acting
as a detector (like in an old time crystal radio set) the coiled
heating element was an inductor and the metal case of the heater was
a sound box! When it was investigated she said she "Didn't mind a bit
and in fact thought it was quite entertaining"!
Today there are so many solid state devices around any home that one
wouldn't be surprised if one could 'hear' things from a ceiling fan,
dimmer switch, or certainly something with audio amplification such as
computer speakers!