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Joined: Dec 2002
Posts: 308
E
Edward Offline OP
Member
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


Thanks
Edward
Joined: Oct 2003
Posts: 31
C
Member
That sounds like a question I might have been asked when I was an apprentice. I'll be looking forward to reading the responses.

Joined: Aug 2002
Posts: 1,691
S
Member
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.

Joined: Jul 2003
Posts: 394
B
Member
How about a bad neutral somewhere. When the toaster is on, it puts "objectionable current" on the ground which the electronics don't like.

Joined: Oct 2003
Posts: 289
:
Member
if the toaster is controlled ba a triac, this could explain the noise.

Joined: Aug 2001
Posts: 7,520
P
Member
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?

Joined: Mar 2002
Posts: 582
R
Ron Offline
Member
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.


Ron
Joined: Oct 2000
Posts: 2,722
Broom Pusher and
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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


Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!

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