I think I need Bobs help?

[9fingers]

Up to a point XY you are correct. Digital coding schemes are chosen to tolerate a degree of interference especially interference that they cause themselves from digital signals in the adjacent channel. But they fail in a digital on/off manner as well.
You may recall from analogue TV days that porr signals caused an ever mors 'snowy' picture and even when the picture was not viewable, you could still see outlines and things moving about. On digital TV the picture stays 99.9% perfect as signal levels drop (or interfence levels rise) and then collapse dramatically into coarse pixellation blocks as the digital decoder gives up and freezes. It tries to compare the previous good picture with the incoming data stream and gives a software estimate of what the next frame should be but after a while the new picture is so far removed from the last decent one it gives up until it can make sense of the data stream once more.

hth

Bob

 

[Eric The Viking]

Bob's right but it's half the problem.

The other half is that sparking erodes the carbon brushes and the commutator of the motor, leading to premature failure. It's just like across the points of a distributor, the suppressors help to reduce this effect (as well as reducing the interference on car radios).

In any case, a spark is a broadband transmitter - it theoretically radiates on every frequency - so the interference is likewise across all frequencies. It doesn't need to be a radio receiver to be susceptible. Anything with a high-impedance analogue source of some sort and a lot of gain following it (amplification) will be affected if it isn't well screened. There's a lot of that stuff around some areas in hospitals (EEG and ECG machines, and some modern image-intensified x-ray machines, for example, all deal in very small signals), which is one reason why they're sniffy about mobile 'phones.

E.

 

[rannndy]

http://www.youtube.com/watch?v=XAot9jI29aA

 

[9fingers]

http://www.youtube.com/watch?v=XAot9jI29aA

=D> =D> =D>

 

[xy mosian]

Thanks Bob, a good explanation.

rannndy, great stuff, I've seen it before, but it's still great. Some may say it's a fake, but who cares it's still makes me laugh.
xy

 

[Hudson Carpentry]

Well its obviously staged for comical reasons but its all real in terms of the belt sander pulling him. I have seen that before and many more where they are sitting on the sander and it moves them. Myself have chased the other half and kids out my shop by letting it go on the floor and I have ridden mine for a few seconds to see if its poss. I wouldn't do it again unless I brought a cheap model in fear of causing the tool damage.

Anybody seen the old TV show Power Tool races, that had its funny moments.