Author Topic: Magnetic components.  (Read 1856 times)

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Offline G7PSK

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Magnetic components.
« on: March 15, 2012, 03:50:15 pm »
I have just found that all the capacitors that I have are made with iron or steel connecting wires while all the resistors have copper wires on further trial I found that the majority of metal oxide resistors are strongly magnetic on the main body. has any one else found this. Also does any one know what the metal film resistors are made from as I understood that it was tin oxide but I tin is not magnetic.
 

Offline T4P

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Re: Magnetic components.
« Reply #1 on: March 15, 2012, 04:43:52 pm »
Hmm , just a short check on wiki claims < note the use of the word 'claims'

Tin oxide for metal oxides ... Hmm , no idea .

Quote
Metal film resistors are usually coated with nickel chromium (NiCr), but might be coated with any of the cermet materials listed above for thin film resistors. Unlike thin film resistors, the material may be applied using different techniques than sputtering (though that is one such technique). Also, unlike thin-film resistors, the resistance value is determined by cutting a helix through the coating rather than by etching. (This is similar to the way carbon resistors are made.) The result is a reasonable tolerance (0.5%, 1%, or 2%) and a temperature coefficient that is generally between 50 and 100 ppm/K.[7] Metal film resistors possess good noise characteristics and low non-linearity due to a low voltage coefficient. Also beneficial are the components efficient tolerance, temperature coefficient and stability.[5]
NiCr ? Not much of a idea anyway .

I tried your theory and yes , they all stick , my metal film , carbon film , all of them stick .
I have a odd 5% resistor in a blue case . Hmm . It sticks too .
 

Online westfw

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Re: Magnetic components.
« Reply #2 on: March 15, 2012, 07:41:52 pm »
Steel end caps crimp the leads onto the ceramic body.  Many data sheets have a detailed drawing.
 

Offline siliconmix

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Re: Magnetic components.
« Reply #3 on: March 16, 2012, 10:18:03 pm »
yep mine all stick.it can't be a problem though.i dont use smd's do they stick?
 

Offline robrenz

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Re: Magnetic components.
« Reply #4 on: March 17, 2012, 01:53:42 am »
I think the metalization on the ends of smd resistors is nickel and nickel is magnetic.  (not the resistive element)

Offline siliconmix

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Re: Magnetic components.
« Reply #5 on: March 17, 2012, 07:38:44 am »
easy to pic up if you drop a load :D
 


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