I'm hearing a faint, dull, intermittent "chirp" sound over my speakers.
It's a recent phenomena.
"chirp..chirp,...... chirp............chirp...chirp....."
There are long periods of silence (no chirps) also (like an hour ?)....then they start again.
The strange thing is the sounds are coming over both my stereo systems, on opposite sides of my house.
The only thing common to both systems is:
....AC line
....Cable TV/internet
System 1 is connected to my computer (w/ cable internet)
System 2 is connected to TV Cable box.
I'll try disconnecting my cable tonight...see if that is the source.
Any other tips ?
It's a recent phenomena.
"chirp..chirp,...... chirp............chirp...chirp....."
There are long periods of silence (no chirps) also (like an hour ?)....then they start again.
The strange thing is the sounds are coming over both my stereo systems, on opposite sides of my house.
The only thing common to both systems is:
....AC line
....Cable TV/internet
System 1 is connected to my computer (w/ cable internet)
System 2 is connected to TV Cable box.
I'll try disconnecting my cable tonight...see if that is the source.
Any other tips ?
I run a pro audio repair shop. One time I had an amp on the bench that would make an electronic noise for maybe 40 seconds and then stop. it did this like clockwork every minute and a half or thereabouts. it was only a bit of luck I left it running while I stepped outside a moment for fresh air and saw the traffic light at the end of the block cycling, and every time the light was red one direction I got the noise. The rest of the light cycle, there was no noise. There was a noisy triac circuit in the traffic light.
Point is, your electrical environment extends farther than you might think. In my case, the noise was riding the AC wires, but you can also have radiated noise as well.
Point is, your electrical environment extends farther than you might think. In my case, the noise was riding the AC wires, but you can also have radiated noise as well.
I´m pretty sure it´s no radar station and no mobile phone because I heard the same thing when I lived on the country side (far from radar stations) in seventies (mobile phones not invented yet). I asked an electrician about it and he told me it was a "Rundsteuersignal".
I don´t know the appropriate english translation, but basically it´s a 1332 Hz signal on the power line used as a simple form of Power Line Communication by energy suppliers.
It´s about 1-4% of the nominal AC voltage.
Here is a scope shot:
http://images.vogel.de/vogelonline/bdb/521200/521274/4.jpg
Edit, found an english text about it:
http://www.anime-za.net/tech/ripple_index.html
I don´t know the appropriate english translation, but basically it´s a 1332 Hz signal on the power line used as a simple form of Power Line Communication by energy suppliers.
It´s about 1-4% of the nominal AC voltage.
Here is a scope shot:
http://images.vogel.de/vogelonline/bdb/521200/521274/4.jpg
Edit, found an english text about it:
http://www.anime-za.net/tech/ripple_index.html
It could be caused by a countless number of different things. This is ablog about one person's search for interference.
"The EMI-RFI page"
EMI - RFI page
"The EMI-RFI page"
EMI - RFI page
Wireless router...WiFi.
I had the same problem with my amplified computer speaker system until I moved my wireless router to a different location. Chirp... chirp... chirp.
This may sound a bit strange, but you may have some DC offset which is causing rectification of RFI energy. A periodic burst of oscillation on an opamp or power supply regulator would then be detected as a chirp. When I do a bode plot of an unstable power supply regulator you'll hear a chirp on an AM radio when the devices moves from stable to unstable. You could also have a WIFI device which is not Part 15 compliant.
The thing is....I believe all my equipment has an AC line filter on it.
If I were to guess the freq of the chirp...it would be around 5-10 kHz.
But people here are right......test my AC line.....configure my meter to detect spikes, and record them. Also ask neighbors if they are having the same problem. It's quite annoying. Good thing I am no longer in the music/sound recording biz, at my home.
(btw.....I do have a wi-fi router....but it's signal is turned off.......All my stuff is hard-wired......CAT 5)
If I were to guess the freq of the chirp...it would be around 5-10 kHz.
But people here are right......test my AC line.....configure my meter to detect spikes, and record them. Also ask neighbors if they are having the same problem. It's quite annoying. Good thing I am no longer in the music/sound recording biz, at my home.
(btw.....I do have a wi-fi router....but it's signal is turned off.......All my stuff is hard-wired......CAT 5)
Last edited:
Another clue is to try to decipher the chirp to what might be a human activity.
If it was a neighbor's metal welder....it would be long chirps for about a line of welding metal.
But it's not.
If I were to translate the chirps into a possible human activity....it might be like as if someone was photoshopping an image....like many clicks on the mouse. I doubt that is the source.....but that gives you and me an idea of the amount and repetitiveness of the sound.
If it was a neighbor's metal welder....it would be long chirps for about a line of welding metal.
But it's not.
If I were to translate the chirps into a possible human activity....it might be like as if someone was photoshopping an image....like many clicks on the mouse. I doubt that is the source.....but that gives you and me an idea of the amount and repetitiveness of the sound.
Filter or block?
I've been getting the odd chirp, but really only a few times a week.
More bothersome is the transformer hum coming off my amplifiers. My cable supplier came through, rewired the 75 apartments , and gave everyone a free 3 month internet tryout.
Since the hum started within days of (presumably) so many more computers going active than before, I think the two are related.
I've tried a homemade rf filter, an expensive Transparent Ultra filter, and a mid level Monster Cable filter.
The hum is still there.
Do you think it may be dc offset creeping into my system, and do you know of any blockers available in Canada ?
Thanks.
I've been getting the odd chirp, but really only a few times a week.
More bothersome is the transformer hum coming off my amplifiers. My cable supplier came through, rewired the 75 apartments , and gave everyone a free 3 month internet tryout.
Since the hum started within days of (presumably) so many more computers going active than before, I think the two are related.
I've tried a homemade rf filter, an expensive Transparent Ultra filter, and a mid level Monster Cable filter.
The hum is still there.
Do you think it may be dc offset creeping into my system, and do you know of any blockers available in Canada ?
Thanks.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.