Hardware @ uni

I'm planning to play with the hub motor a bit. It is easily removed and as long as the electronics is still functional I'll have a look at the signals going or coming from the 4 pins of the motor.

More than 16500 power-on hours without any trouble. As of lately it started talking to me: "CLICK CLICK CATCHUNK!!!!". I instantly moved my system to a new disk. The smallest one I could get was 500GB. Time is moving fast. ALWAYS MAKE BACKUPS - REGULARLY.

Unfortunately all of these very nice Torx screws don't seem to be metric. At least not M3. I like Torx much better than the common socket head ones.

Time to go 'back to sender'.

That's what I call a lot of corrosion.

It is indeed a BLDC motor. The coils are Y-wound.

It is indeed a BLDC motor. The coils are Y-wound. The left pad goes to the center point N, the remaining are the 3 phases U,V,W. Single-coil-resistance is about 1.6 Ohm. The disk's PCB contains a Hitachi HA13645 driver. Unfortunately I just can't find a datasheet for that. From what I've read so far, driving these with back EMF detection on the un-driven coils could be quite difficult. scholar.lib.vt.edu/theses/available/etd-09152003-171904/u... www.atmel.com/dyn/general/tech_doc.asp?doc_id=10416

Quite silent, compared to usual server room noise. Not a single failure in 3 years 24/7 operation.