i would like to test whether a coil (inductor) is connected in wrong side .... how to do that?
the coil is actually on a harddisk arm (the read head).... there are two tiny pins connecting the start and end of the coil. sometimes they are connected wrongly...
Monkey is not drunk. Today he is overly economical with his words.
What he means is that hard drive media are in a sealed section with an atmosphere devoid of dust particles. If you open that section there will be so many dust particles on the media from the air in your room that they will act like sand paper and ruin the read/write head. They will also block reading and writing of the media portion they are on.
You should buy an inductance meter. If the coils are in series properly, you will get a maximium inductance L. If they are in parallel the inductance will be about L/4. If they are in series the wrong way the inductance will be near zero. All of these values assuming high mutual inductance between the coils.
An isolated coil does not, but with two the mutual inductance does have a polarity. That is why there are dots on the schematics of two coils with mutual inductance.
ok, i will try it out using inductance meter (haven't got such a meter yet) and tried put the result here when i got it
but i did see a circuit just using some comparators to do that detection. i don't know and don't understand what is it the circuit is doing. any clue on this?