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#30510 - 10/21/03 06:10 PM Noise in the electronic equipment?
Edward Offline
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Registered: 12/14/02
Posts: 308
Loc: California
Why would a toaster (a resistive load) create a humming noise in the power supply of an stereo equipment? If it was a microwave i would understand but why a toaster?
Edward
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#30511 - 10/21/03 06:47 PM Re: Noise in the electronic equipment?
Clyde Offline
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Registered: 10/17/03
Posts: 31
Loc: Leamington
That sounds like a question I might have been asked when I was an apprentice. I'll be looking forward to reading the responses.
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#30512 - 10/21/03 07:42 PM Re: Noise in the electronic equipment?
SvenNYC Offline
Member
Registered: 08/19/02
Posts: 1691
Loc: New York City
Does the toaster have any ELECTRONIC components?

For example, some of the fancier toasters have electronic temperature controls to enable the device to consistently produce the same darkness of toast slice after slice.

Some toasters also have an electromagnet that holds the bread grills down when you press the lever instead of a mechanical catch hooked up to the thermostat.

You can tell when you're dealing with one of those when you unplug the toaster and try to press the lever down. It won't stay down. An old-fashioned conventional toaster would let you click the handle in place even if it's not plugged in.
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#30513 - 10/21/03 10:52 PM Re: Noise in the electronic equipment?
Big Jim Offline
Member
Registered: 07/18/03
Posts: 394
Loc: Denver, CO USA
How about a bad neutral somewhere. When the toaster is on, it puts "objectionable current" on the ground which the electronics don't like.
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#30514 - 10/22/03 09:32 AM Re: Noise in the electronic equipment?
:andy: Offline
Member
Registered: 10/18/03
Posts: 289
Loc: Germany
if the toaster is controlled ba a triac, this could explain the noise.
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#30515 - 10/22/03 03:50 PM Re: Noise in the electronic equipment?
pauluk Offline
Member
Registered: 08/11/01
Posts: 7520
Loc: Norfolk, England
Same question as has been put for the amplifier on stage:

Does the hum sound like pure 60Hz AC line noise, or does it have a distinct high-frequency or rasping sound to it?
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#30516 - 10/22/03 05:45 PM Re: Noise in the electronic equipment?
Ron Offline
Member
Registered: 03/13/02
Posts: 582
Loc: White Plains, NY
Only a guess, but measure the voltage at the receptacle where the stereo is plugged in. When the toaster is used, does the voltage drop significantly at the stereo? The amplifier in the stereo might not like a low voltage condition for it transistors to operate in the region they like.
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#30517 - 10/24/03 11:58 AM Re: Noise in the electronic equipment?
Scott35 Offline

Broom Pusher and
Member
Registered: 10/19/00
Posts: 2707
Loc: Anaheim, CA. USA
I agree with Paul.

What type of noise is being observed?;
Is it a "Predictable" pop?
Is it a string of pops and hisses?
Is it a steady hum?
Is it like a Dentist's drill?
Is it all of the above?

Predictable pops would be from the toaster's switch opening and closing.

String of pops and hisses would be thermostatically connected elements going on and off, and maybe sounds coupled from other sources.

Steady hum would be some type of reactive elements' coupling.

Dentist's drill would be Solid State control elements (or other stuff coupled to it).

All above could be anything!!!

Scott35
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