Need advice with non-working 1541 single drive unit

[8 Bit Dreams]

Short story:

got two 1541 floppy disk drives, one of them (Mitsumi) won't read disks giving "FILE NOT FOUND, ERROR"
1. The drive can Initialize on switching on, so i assume it has no defective chips.
2. The drive is unable to format any disk (have tryed many, not only one). i have obtained a copy of the Free Spirit drive alignment software (side A only) and tryed to align the drive with 1541/1571 demo disk with no sucsess (was unable to set the head to any track, however, it shows a track number sometimes for less than a second).
3. Checked the resistance of the head:
red & yellow 15.26 kOhm
red & black 15.26 kOhm
red & blue 15.25 kOhm

yellow & black 16 Ohm
yellow & blue 27.4 Ohm

Black & blue 13.7 Ohm

seems that the head is dead? am i right, or are these measurements ok for Mitsumi/Newtronic drives? - EDITED - no, they are not ok!
If the head is dead, where can i obtain a spare? Looked for them, but didn't found any...

Have looked at this:
http://personalpages.tds.net/~rcarlsen/cbm/1541/1541chip.txt
http://personalpages.tds.net/~rcarlsen/cbm/1541/fix1541.txt
https://www.youtube.com/watch?v=2KuWJVUDc5k
https://www.youtube.com/watch?v=oQCBgaOc_mc
played a lot around, the only thing i haven't done till now - demagnetised the head, as i have no idea how to do it without special tool..
i'm runned out of ideas how to fix it and need some advice please...

EDIT

seems that the dive head is dead, have tryed to swap the board in a working drive and it works with no problems. Semms that red colour line is burned out. So need a drive head or a spare drive mechanism now. If someone has one to sell cheap - please pm me.
regards,

-Cook

 

[Deleted member 14264]

1. The drive can Initialize on switching on, so i assume it has no defective chips.

You assume wrong!

There could be a lot of problems with the analog electronics between the head and the digital circuits responsible for decoding the signals.

I have a board here with faulty components around the u592 amplifiers and it will do exactly the same as your drive. You could also have a faulty capacitor or faulty induction coil used in the bandpass filter.

BTW, Nobody refers to the mechas of 1541 drives as "Mitsumi". The are usually called Alps or Newtronics. Newtronics is a division of Mitsumi so I assume that's what you have.

 

[8 Bit Dreams]

Yes, thank You for Your answer Eslapion, i have already corrected my previous post
further research has shown that the logic board works good with other floppy mechanism, so i focused on the head. Turned out that the resistance measurment is not the same as on a working drive
looking for working Newtronics drive head now (i don't belive this fault can be fixed)...

 

[Deleted member 14264]

... further research has shown that the logic board works good with other floppy mechanism, so i focused on the head.

I guess this narrows it down clearly then.