Washing machine interfering with my computer?

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Copycats

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My bedroom is next to the laundry room in my house and when the machine is running, I can hear some clicking sound from time to time from my speakers hooked up to the computer in my bedroom. I have tried plugging the washing machine into another wall outlet as well as plugging my computer to another outlet, but the problem remains. If I shut the computer off but keep my sound system on, the sound goes away.

I'm just wondering if this would have a negative effect on my computer hardware somehow, I do have a pretty robust surge protector (UPS) connected with my computer.

Any idea? Thanks!
 
I am skeptical that it's because of your washing machine or your power outlet.

It's more likely that you are getting interference from you 3.5mm jack on your motherboard or your case.

I know when I plug my headset into my case I get some interference.

Either way I doubt it would have an detrimental effect to your computer or sound system.
 
relay arc in washer= spark gap transmitter

its RF, not coupled through the AC
 
jojo69 said:
relay arc in washer= spark gap transmitter

its RF, not coupled through the AC
Click to expand...

Ahh ... what's a relay arc? and how the heck the washing machine has a spark gap generator? :eek:

If it's true. the RF generated could do anything to the computer?

Thanks!
 
ahuang0284 said:
I am skeptical that it's because of your washing machine or your power outlet.

It's more likely that you are getting interference from you 3.5mm jack on your motherboard or your case.

I know when I plug my headset into my case I get some interference.

Either way I doubt it would have an detrimental effect to your computer or sound system.
Click to expand...


pretty sure it's the washing machine, when it's not running, I don't hear anything ...
 
jojo69 said:
relay arc in washer= spark gap transmitter

its RF, not coupled through the AC
Click to expand...

agree; maybe try playing with the spread spectrum switch in BIOS. sounds like the washer and the computer all run from the same circuit, no matter which outlet you are testing
 
Get a 12 gauge extention cord and plug the computer or washing machine into outlets farther away. Does your house have circuit breakers or fuses?
 
Copycats said:
Ahh ... what's a relay arc? and how the heck the washing machine has a spark gap generator? :eek:

If it's true. the RF generated could do anything to the computer?

Thanks!
Click to expand...

There are relays that turn the motor and pump on and off at the appropriate time in the cycle. When a relay changes state there is an instant where the contacts are not touching but still close enough for the voltage available to jump the air gap. If you were watching an open frame relay in a dark room you would see the blue spark.

No, it is fine, just in the audio is all.
 
that ac line filter i posted is only good up to 7 amps. so, i guess only consider with a sub-700 watt system

[edit2] tripp lite stuff; http://www.tessco.com/products/displayProducts.do?groupId=050&subgroupId=14 looks better and cheaper.

idk, a lot of surge protectors offer line filtering, but they have varying ratings for the db drop. 'power conditioning' isn't something i had considered before for audio systems on an extreme level, but as it's obviously an issue for you, i'd say your existing equipment isn't up to the task
 
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I'd doubt his system users more than 7 AMPs. (770W)
 
jojo69 said:
There are relays that turn the motor and pump on and off at the appropriate time in the cycle. When a relay changes state there is an instant where the contacts are not touching but still close enough for the voltage available to jump the air gap. If you were watching an open frame relay in a dark room you would see the blue spark.

No, it is fine, just in the audio is all.
Click to expand...

That makes a lot of sense. Thanks, JoJo! So basically, moving the computer far enough from the washer should eliminate the sound completely? I guess.

Strangely, the machine is running right now but I can't hear a thing. But It's worse sometimes than others.
 
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SinShiva said:
that ac line filter i posted is only good up to 7 amps. so, i guess only consider with a sub-700 watt system

[edit2] tripp lite stuff; http://www.tessco.com/products/displayProducts.do?groupId=050&subgroupId=14 looks better and cheaper.

idk, a lot of surge protectors offer line filtering, but they have varying ratings for the db drop. 'power conditioning' isn't something i had considered before for audio systems on an extreme level, but as it's obviously an issue for you, i'd say your existing equipment isn't up to the task
Click to expand...


HA! I'm actually using 2 surge protectors with the computer: the main power is plugged into this and the external hard drive is plugged into exactly one of those ISOBARs you linked. ;)

I think as Jojo mentioned, the noise is probably not in the circuit, it's RF.
 
I agree with the earlier posters; this sounds very much like classic RF interference caused by a mechanical relay, which is radiated. In the "old days" (no, before my time....:D) early radio transmitters were called "spark gap" transmitters and operated by creating a high voltage spark across an air gap. That would release an amazingly powerful burst of broadband radio energy. What you have is a small version of the same thing. As such, line filters for the AC mains probably won't do squat.

I don't think it will do any long term harm, unless the "pops" are loud enough to eventually overstress one of the drivers in your speaker systems. If it bothers you, get six of these and put them on both ends of the speaker wires, and both ends of the cable that runs from your PC to the speakers. Basically, any audio cable you have in your setup. That should help a lot.
 
I doubt it's RF. If it were RF, it'd still happen when his computer was off, since said computer is (presumably) shielded by a grounded metal chassis, and thus wouldn't be affected.

My gut feel is that the UPS's Trim is cutting in when the washer causes the voltage to sag. The waveform mismatch can be enough to induce ground-plane shifts in the line-out.

If you're really worried about it, buy a double-conversion UPS and plug both computer and sound system into it. It'll probably run you north of a grand, but that's the price of enterprise hardware.
 
XenIneX said:
I doubt it's RF. If it were RF, it'd still happen when his computer was off, since said computer is (presumably) shielded by a grounded metal chassis, and thus wouldn't be affected.

My gut feel is that the UPS's Trim is cutting in when the washer causes the voltage to sag. The waveform mismatch can be enough to induce ground-plane shifts in the line-out.

If you're really worried about it, buy a double-conversion UPS and plug both computer and sound system into it. It'll probably run you north of a grand, but that's the price of enterprise hardware.
Click to expand...

Depends, you make a good point but we don't really have enough information. RF shielding of computer cases leaves a LOT to be desired in my experience. Also, we don't know if he has a mic or other input plugged into the card. In the RF world we call input wires "antennas" and the interference could be riding into his amplifiers.

A few ferrite chokes is a hell of a lot cheaper test than a fancy UPS.
 
A quick test would be to get a long extension cord of decent size (gauge) and run it across the house to another outlet and plug the PC and all peripherals into that. If the issue is conducted AC noise, that will eliminate or at least change it.

I'm still betting on radiated noise....and, the ferrites should make quite a difference in it.....:cool:
 
XenIneX said:
I doubt it's RF. If it were RF, it'd still happen when his computer was off, since said computer is (presumably) shielded by a grounded metal chassis, and thus wouldn't be affected.
Click to expand...

When the system is off, the input to the speaker amp presents a relatively high impedance and introducing noise onto that line won't make any sounds on the output. Once you turn that amplifier on, it doesn't take much of a signal to make a 'pop' on the output. My best guess is that the input is functioning like an antenna and coupling the RF into the amp, which amplifies it and causes the issue. Those ferrites are cheap enough that if a guy were to order some, it's cheap insurance to go ahead and put them on the speaker cables as well. It is possible but not as likely that the speaker cables are the antennas that are conducting the RF energy back into the amp.....
 
jojo69 said:
Depends, you make a good point but we don't really have enough information. RF shielding of computer cases leaves a LOT to be desired in my experience. Also, we don't know if he has a mic or other input plugged into the card. In the RF world we call input wires "antennas" and the interference could be riding into his amplifiers.

A few ferrite chokes is a hell of a lot cheaper test than a fancy UPS.
Click to expand...

Great point! I do have a mic plugged in! Okay, I will try a few tests by changing only one variable at a time:

1. First, unplug or disable the mic

2. Remove the UPS and plug the computer into a power strip with only surge protection

3. As BlindedbyScience suggested, I will run a long cord to another outlet outside my room, across the hallway and see what happens.

4. If I have a chance, I will move the computer to another room, then run a long cable back to plug the computer back in an outlet in my bedroom.

5. Not going to get an expensive UPS. Sorry, Xenlne :cool: But I may look into the ferrite thingy jojo was talking about.


Great insights! Will report back!
 
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BlindedByScience said:
When the system is off, the input to the speaker amp presents a relatively high impedance and introducing noise onto that line won't make any sounds on the output. Once you turn that amplifier on, it doesn't take much of a signal to make a 'pop' on the output. My best guess is that the input is functioning like an antenna and coupling the RF into the amp, which amplifies it and causes the issue. Those ferrites are cheap enough that if a guy were to order some, it's cheap insurance to go ahead and put them on the speaker cables as well. It is possible but not as likely that the speaker cables are the antennas that are conducting the RF energy back into the amp.....
Click to expand...

I also doubt the speaker cables are part of this ...
 
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