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#1
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Power Circuit Noise?
Hi,
I just started to hear power circuit noise on my PC speaker system. If I turn on my paper shredder, I can hear it on my PC speaker system. Do I have a ground issue? How can I fix this? Thanks, Dan |
#2
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Hi,
I just started to hear power circuit noise on my PC speaker system. If I turn on my paper shredder, I can hear it on my PC speaker system. Do I have a ground issue? How can I fix this? It might be an issue with the ground. It might also be a problem with the hot or neutral connnections on your circuit. No way to tell for sure at a distance. I would suggest having a competent licensed technician check out your wiring. If you've got a loose wire somewhere in the walls (at an outlet or circuit breaker) or have a circuit breaker going bad, this could create a very real shock or fire hazard. If you're seeing odd signs, such as a light getting *brighter* when your fridge starts up or you turn on another appliance (rather than getting *dimmer*), or if any of your appliances have started running slower than usual, I'd suggest calling the electric company. These can be symptoms of an "open neutral", and the resulting low and high voltages can damage things in the house. [We had this happen a couple of months ago, when a squirrel chewed through the neutral wire right near the power pole.] -- Dave Platt AE6EO Hosting the 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! |
#4
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In , on 05/13/05
at 01:05 AM, Dan said: I just started to hear power circuit noise on my PC speaker system. If I turn on my paper shredder, I can hear it on my PC speaker system. Do I have a ground issue? How can I fix this? Dave and Steve's advice is reasonable. Have you changed anything? Sometimes the quality of computer speakers and shredder motors are dreadfully low and such problems are expected. Are there any other symptoms beyond the computer speakers? If you use an antenna for your TV, how is the TV picture? Can you see any interference when the shredder runs? Tune an AM portable radio between stations at the upper end of the band and run the shredder. Is the radio upset? If so, move the shredder to another circuit and listen to the radio again. Same results? If so, the shredder has a problem. If not, there is something odd about the original circuit (and we can't give the shredder a clean bill of health). If you purchased the lowest price possible surge protector outlet strip, the technology could be taking it's revenge. Cheap (less than about $20.00) outlet strips don't protect much. In general, as you walk around listening to your radio, spots where the noise seems concentrated are "interesting". The spot could be near the primary source (bad motor, bad connection) of the noise or a weak spot in the system that should be evaluated. ----------------------------------------------------------- spam: wordgame:123(abc):14 9 20 5 2 9 18 4 at 22 15 9 3 5 14 5 20 dot 3 15 13 (Barry Mann) [sorry about the puzzle, spammers are ruining my mailbox] ----------------------------------------------------------- |
#5
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On 5/12/2005 10:49 PM, Steve Urbach wrote:
On Fri, 13 May 2005 01:11:41 -0000, (Dave Platt) wrote: If I turn on my paper shredder, I can hear it on my PC speaker system. Besides what others said. Doed your shredder use a Brush (universal) type motor? The brushes may be dirty or worn causing arcing. IMHO Shredders, power staplers, VACUUM Cleaners do not belong on a computer circuit and NEVER plugged into the same outlet STRIP. FWIW the surge circuit is now probably dead or weak if you *have* used this equipment on a surge-outlet strip. The shredder is plugged directly in a wall outlet of the other side of the room from where my PC is hooked up. |
#6
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On Fri, 13 May 2005 14:56:23 -0500, Dan wrote:
On 5/12/2005 10:49 PM, Steve Urbach wrote: On Fri, 13 May 2005 01:11:41 -0000, (Dave Platt) wrote: If I turn on my paper shredder, I can hear it on my PC speaker system. Besides what others said. Doed your shredder use a Brush (universal) type motor? The brushes may be dirty or worn causing arcing. IMHO Shredders, power staplers, VACUUM Cleaners do not belong on a computer circuit and NEVER plugged into the same outlet STRIP. FWIW the surge circuit is now probably dead or weak if you *have* used this equipment on a surge-outlet strip. The shredder is plugged directly in a wall outlet of the other side of the room from where my PC is hooked up. That does not stop the Electo-Magnetic Noise generated if it has a noise spewing motor. Barry has the right ideas on isolating the problem. Fix the CAUSE. If the speakers are the only device affected (not heard on the AM radio or other devices), then a overly sensitve (poorly shielded) Speaker is the cause. Note: Speaker (amplifier) signal leads should not be tightly bundled with AC power cords. , _ , | \ MKA: Steve Urbach , | )erek No JUNK in my email please , ____|_/ragonsclaw , / / / Running United Devices "Cure For Cancer" Project 24/7 Have you helped? http://www.grid.org |
#7
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Steve Urbach wrote:
On Fri, 13 May 2005 14:56:23 -0500, Dan wrote: On 5/12/2005 10:49 PM, Steve Urbach wrote: On Fri, 13 May 2005 01:11:41 -0000, (Dave Platt) wrote: If I turn on my paper shredder, I can hear it on my PC speaker system. Besides what others said. Doed your shredder use a Brush (universal) type motor? The brushes may be dirty or worn causing arcing. IMHO Shredders, power staplers, VACUUM Cleaners do not belong on a computer circuit and NEVER plugged into the same outlet STRIP. FWIW the surge circuit is now probably dead or weak if you *have* used this equipment on a surge-outlet strip. The shredder is plugged directly in a wall outlet of the other side of the room from where my PC is hooked up. That does not stop the Electo-Magnetic Noise generated if it has a noise spewing motor. Barry has the right ideas on isolating the problem. Fix the CAUSE. If the speakers are the only device affected (not heard on the AM radio or other devices), then a overly sensitve (poorly shielded) Speaker is the cause. Note: Speaker (amplifier) signal leads should not be tightly bundled with AC power cords. I don't have an AM radio available right now. If I unplug my speaker system from the PC, then I don't hear the shredder. So the noise is traveling through my PC sound card, right? When I get the AM radio. Should I plug it into AC power or run on battery? |
#8
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On Sat, 14 May 2005 01:33:38 GMT, Dan wrote:
When I get the AM radio. Should I plug it into AC power or run on battery? Run it on battery. Tune BETWEEN stations where the AGC circuit allows maximum RF gain. Determine where the Ferrite loopstick is located in the radio, (usually in the top and horizontal). Hold the radio with your hands as far away from the loopstick as possible. The sides of the radio are the pickup direction. rotate/tilt the radio twoard suspected noise sources and listen. Move about, when you rotate for peak noise, does the edge point toward the the same item? Remember, the pickup is off both edges, that is why circling is best to locate the noise. Remember to tilt up for ovrhead sources like gas discharge light fixtures, utility pole insulators (or dow if on a upper storey). I found bad utility pole insulators that were messing up my TV picture that way (BTW they will normally make noise in foggy/moist weather). Where do the speakers get their power? Plug a set of headphones into the sound card, carefully test levels before placing over your ears. What do you hear that way? Plug the speakers into a Walkman type device (on battery, preffered), What happens? Tracking noise by remote G is difficult. , _ , | \ MKA: Steve Urbach , | )erek No JUNK in my email please , ____|_/ragonsclaw , / / / Running United Devices "Cure For Cancer" Project 24/7 Have you helped? http://www.grid.org |
#9
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In , on 05/14/05
at 03:41 AM, Steve Urbach said: I found bad utility pole insulators that were messing up my TV picture How long did it take the power utility to own the problem? My father had that problem. It took me months to convince him to walk the block with his radio. After he identified the poles, the utility dragged its heals for another few months until my dad organized a neighborhood "call-in". Eventually, they brought around their special diagnostic van, scanned the neighborhood, then replaced most of the insulators on the block. ----------------------------------------------------------- spam: wordgame:123(abc):14 9 20 5 2 9 18 4 at 22 15 9 3 5 14 5 20 dot 3 15 13 (Barry Mann) [sorry about the puzzle, spammers are ruining my mailbox] ----------------------------------------------------------- |
#10
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On Sat, 14 May 2005 22:11:45 -0400, (Barry Mann) wrote:
In , on 05/14/05 at 03:41 AM, Steve Urbach said: I found bad utility pole insulators that were messing up my TV picture How long did it take the power utility to own the problem? My father had that problem. It took me months to convince him to walk the block with his radio. After he identified the poles, the utility dragged its heals for another few months until my dad organized a neighborhood "call-in". Eventually, they brought around their special diagnostic van, scanned the neighborhood, then replaced most of the insulators on the block. About 2 years to FIX. The excuse was "We will be renovating the distribution in your area". Our area was a weird 1000V grid and could not be cross connected int other neighborhoods that had the more standard 1200V grid. They replaced everything on the pole and power outages became rare. , _ , | \ MKA: Steve Urbach , | )erek No JUNK in my email please , ____|_/ragonsclaw , / / / Running United Devices "Cure For Cancer" Project 24/7 Have you helped? http://www.grid.org |
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