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Posted By: Edward Noise in the electronic equipment? - 10/22/03 01:10 AM
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
Posted By: Clyde Re: Noise in the electronic equipment? - 10/22/03 01:47 AM
That sounds like a question I might have been asked when I was an apprentice. I'll be looking forward to reading the responses.
Posted By: SvenNYC Re: Noise in the electronic equipment? - 10/22/03 02:42 AM
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.
Posted By: Big Jim Re: Noise in the electronic equipment? - 10/22/03 05:52 AM
How about a bad neutral somewhere. When the toaster is on, it puts "objectionable current" on the ground which the electronics don't like.
Posted By: :andy: Re: Noise in the electronic equipment? - 10/22/03 04:32 PM
if the toaster is controlled ba a triac, this could explain the noise.
Posted By: pauluk Re: Noise in the electronic equipment? - 10/22/03 10:50 PM
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?
Posted By: Ron Re: Noise in the electronic equipment? - 10/23/03 12:45 AM
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.
Posted By: Scott35 Re: Noise in the electronic equipment? - 10/24/03 06:58 PM
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!!! [Linked Image]

Scott35
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