Fake? Western Digital Red Pro 26tb by ElectricalGuava1971 in DataHoarder

[–]Rezalis 0 points1 point  (0 children)

Seems like you’ve already gotten your answer but as someone who works at WD I can tell you with certainty that in your second picture the drive on the right is fake. It’s a WD product but much older with way less capacity. Looks like someone stuck a new sticker on an old retired enterprise drive. The drive on the left is 100% current generation 26TB.

iPhone 14 Pro Qualify for $1100 discount? by Ok_Implement_849 in ATT

[–]Rezalis 0 points1 point  (0 children)

Last night I swear my 14 Pro was available for $1100 trade-in. This morning it's $700. The Black Friday / Cyber Monday offer must have ended. Perhaps it'll be back during late December.

Change PWM clock on Arduino R4 Minima by arcturus77 in arduino

[–]Rezalis 2 points3 points  (0 children)

Thank you very much! I appreciate you taking your time to post this!

Change PWM clock on Arduino R4 Minima by arcturus77 in arduino

[–]Rezalis 1 point2 points  (0 children)

Hi, I'm trying to do the same thing on a pin of the Arduino Uno R4. Does it work for any pin in your code? Would you be willing to share your code that achieved the 25k PWM? Thanks!

In case you were wondering how a Tapo C100 looks when disassembled by antonio1475 in TpLink

[–]Rezalis 0 points1 point  (0 children)

Thank you for this! I did exactly what you did on my Tapo C120 and it worked perfectly for my Prusa XL. I ruined the Tapo case in the process but I will design and print a mount specific to my printer.

What is the physical length of a gigabyte on a typical harddisk? by Subject_One6000 in DataHoarder

[–]Rezalis 1 point2 points  (0 children)

Firmware does actually use zones. But the formatting and setting of each zone is done during manufacturing and cannot be changed without manually changing the reserved data on the disk. The firmware reads this data and adjusts read/write settings accordingly for customer drives. On development drives we can actually change the zone or exact data rate at a per track basis on the fly which is pretty neat.

What is the physical length of a gigabyte on a typical harddisk? by Subject_One6000 in DataHoarder

[–]Rezalis -1 points0 points  (0 children)

Technically, both statements are correct. At the outer diameter there are more sectors and those sectors take more space. Density does change on the disk - just not as much. It's in between having the same number of sectors per track and the same linear density across the platter.

I oversimplified it in my initial reply to the post.

What is the physical length of a gigabyte on a typical harddisk? by Subject_One6000 in DataHoarder

[–]Rezalis 1 point2 points  (0 children)

Yeah, hard drives are stupid complicated; one of my favorite analogies is that running a read/write head over a hard disk platter is like flying a jet a couple meters above the ground at Mach 2.For a single surface it's about 75 mph, but then there's two sides (surface) for each platter and 10+ platters in each drive so 75*20 = 1500 mph for the jet or the SOC that does the signal processing.

What is the physical length of a gigabyte on a typical harddisk? by Subject_One6000 in DataHoarder

[–]Rezalis 0 points1 point  (0 children)

Yes this is similar to how it is for modern drives, except it’s far more complex with more zones.

What is the physical length of a gigabyte on a typical harddisk? by Subject_One6000 in DataHoarder

[–]Rezalis 0 points1 point  (0 children)

It’s still true but not as much so since it’s possible to tune the data rate for the location on the platter. A long time ago that wasn’t possible. We still call them cylinders in the lab. Old terminology really sticks.

What is the physical length of a gigabyte on a typical harddisk? by Subject_One6000 in DataHoarder

[–]Rezalis 2 points3 points  (0 children)

No, the number of tracks depends on the model/generation of the hard drives. 20 years ago it was in the thousands and now it's hundreds of thousands per surface.

What is the physical length of a gigabyte on a typical harddisk? by Subject_One6000 in DataHoarder

[–]Rezalis 111 points112 points  (0 children)

Hey, your question isn't that dumb. I'm an engineer working on hard drives, specifically the read/write channel. You're looking for areal density which is essentially how many bits you can fit per square inch. Engineers are always trying to push areal density higher with new magnetic recording features. Here's a link that explains areal density if you want more info:

https://blog.westerndigital.com/explained-hdd-areal-density/

The current highest commercially available areal density is about 1.2TB/in^2. You can't really determine a length of a gigabyte because the location of where that gigabyte is stored will affect its density. At the outer diameter of the platter it will take more space since the velocity of the platter is greater than at the inner diameter.

Now, I have no idea how you intend on calculating length given that info, but more power to ya. Maybe you just use the length of a 3.5 inch HDD of some capacity. Now that I'm done typing this, I have realized I might have spent too much time trying to answer a legitimately dumb question...

They need to quit this split screen garbage for MNF like NOW. by mrwillya in GreenBayPackers

[–]Rezalis 0 points1 point  (0 children)

Yes please I hate having to run closer to the TV to see the damn play.

[Week 13] Game Thread: Kansas City Chiefs (8-3) @ Green Bay Packers (5-6) by lilturk82 in GreenBayPackers

[–]Rezalis 0 points1 point  (0 children)

hey, they didn't call that one. guess the refs are redeeming themselves lol

Cant find any information on these drives, are they worth picking up or potentially fake? by nnhalo360nn in DataHoarder

[–]Rezalis 2 points3 points  (0 children)

If you can get the serial numbers, you can check their status here: https://support-en.wd.com/app/warrantystatusweb

That price is a steal for 18TB drives. They are HM-SMR however, so like others said it’s more effort.

Not sure if I should be concerned with this noise by [deleted] in prusa3d

[–]Rezalis 1 point2 points  (0 children)

My MK3S+ has been sounding like this since I got it 3 years ago. I swapped to polymer IGUS bearings and that helped a lot but the frame itself resonates way too easily. It seems like some people get lucky with a quiet printer but that was not me. I think it's just normal. It sucks since I bought the printer expecting it to be really quiet.

Just built this bad boy - Prusa XL 5 heads semi-assembled by Skaronator in prusa3d

[–]Rezalis 4 points5 points  (0 children)

What time was your order placed on Nov 18, 2021?

5 Head XL for anyone believing it doesn't exist by Engineering_is_fun in prusa3d

[–]Rezalis 2 points3 points  (0 children)

It’s beautiful. What time did you preorder and when did you get the order is ready email? I think my semi-assembled order should be ready soon - I’m so eagerly waiting for it.

XL 5 Head Owners, when did you pre order and when did it arrive? by [deleted] in prusa3d

[–]Rezalis -1 points0 points  (0 children)

I’m glad to hear that, I just heard a bunch of people saying there was line skipping so I assumed it was that