FDS Services (Calibration, Disk Refresh)

Started by Stephen, June 27, 2022, 03:17:05 pm

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Stephen

June 27, 2022, 03:17:05 pm Last Edit: October 12, 2022, 07:31:28 pm by Stephen
I'm offering two tiers of FDS disk drive HVC-022 calibration services and disk-refresh. I am located in California.

Base - $40 (eBay Listing)
Intended for general use with the Famicom Disk System Drive or Twin Famicom.
  • Replace Belt
  • Degauss Head
  • Spindle Alignment
  • Basic Spindle Speed calibration
  • Basic Head Calibration
  • Clean excess grease and refresh with white lithium grease where required for performance
  • Cleaning internal disk drive where required for performance

Premium - $75
Intended for use with the FDS Stick (e.g., backing up disks, refreshing disk images).
  • All of the items listed in Basic
  • Premium Spindle Speed calibration
  • Premium Head calibration


Additional Services:

Drive Write Protection Bypass - $30
Disable write protection on your HVC-022 Disk Drive.
  • Bypass Power Supply Write Protection
  • Bypass FD3206 Drive Protection

Disk Refresh - $30
Perfect for your worn or out of calibration disks.
  • Provide a worn or out-of-calibration disk
  • I will capture your save data and disk image
  • I will degauss the disk so that it's back to "virgin" flux (like the day it was made)
  • I will re-write the captured data with perfect calibration.
  • Enquire for multiple disk discounts

FDS Stick -> FDS Disk Drive Cable - $30
Tidy cabling available for use of FDS Stick and FDS Disk Drive.
  • Cables are typically between 3-6" and may vary.
  • Each end of the cable is labelled "top". Correct orientation must be observed.

FAQ:
Disk errors can still occur on calibrated disk drives. How?
  • Disks that were re-written with a disk copier (e.g., Disk Hacker) on a "basic" or otherwise poorly aligned Famicom disk drive HVC-022 will not read accurately and may fail.
  • Inaccurate disks often will only work on the drive they were written on
  • These disks may need to be refreshed
How do you provide calibration (disk drives, disk refresh)?
  • I calibrate disk drives using a known-good OEM disk.
  • I write calibrated disk by recording the existing uncalibrated disk data and writing it back with a calibrated disk drive.
  • Disk refresh service does not include any label or insert reproductions.
  • Disk refresh service does not include writing any other game type than the original game provided.
What is the difference between "basic" and "premium" calibration?
  • Basic calibration is intended for use with the Famicom HVC-023 RAM cartridge and requires "normal" accuracy.
  • Premium calibration is intended for use with the FDS Stick and requires significantly improved accuracy.

Terms of Service
  • 6 month warranty from date of return shipping. Warranty void if tamper sticker damaged or removed. Warranty service does not cover shipping.
  • Shipping (to, return) not included.
  • North American customers preferred.
  • International customers please enquire.
  • I do not offer returns or refunds on my services.
  • Orders will be shipped when payment is released.
  • My services do not include repairing broken components. Items received as broken will be returned in the state they arrived.
  • My services do not include general cleaning. Cleaning will only be performed where functionally necessary.
  • Save data may not be present in refreshed disks which were unreadable.

ericj

What's the difference between:

Basic Spindle Speed calibration
Basic Head Calibration

and

Premium Spindle Speed calibration
Premium Head calibration?

Stephen

June 27, 2022, 09:08:26 pm #2 Last Edit: June 29, 2022, 08:25:36 am by Stephen
Quote from: ericj on June 27, 2022, 06:47:45 pmWhat's the difference between:

Basic Spindle Speed calibration
Basic Head Calibration

and

Premium Spindle Speed calibration
Premium Head calibration?
Basic calibration is intended for use on the HVC-023 RAM cartridge. Premium is intended for use with the FDS Stick, which requires significantly greater calibration accuracy to reliably copy and write archival backups / refresh of games already owned.

hgage2003

June 29, 2022, 12:51:16 am #3 Last Edit: June 29, 2022, 12:57:10 am by hgage2003
Can you make Ram Adapter to Twin Famicom cable?

Stephen

Quote from: hgage2003 on June 29, 2022, 12:51:16 amCan you make Ram Adapter to Twin Famicom cable?
I haven't made a cable for the Twin Famicom before. However, I can use the pinout from the bottom of the FDSStick website (or another resource if you provide it). My biggest concern is that I don't own a Twin Famicom so I cannot test my work before shipping it out. Feel free to DM me know if you're still interested.

P

So Premium is basically making it factory aligned so that it can write disks properly?

Stephen

June 29, 2022, 05:08:41 pm #6 Last Edit: June 29, 2022, 05:46:42 pm by Stephen
Quote from: P on June 29, 2022, 01:03:17 pmSo Premium is basically making it factory aligned so that it can write disks properly?
Conceptually, yes - but to my knowledge no one really has a clear idea of what factory alignment was (quantifiably).

I'm pretty confident factory aligned disk drives were limited only to the 10% margin of error which the RAM cartridge ROM accepts. Why? Because I've calibrated nearly a dozen (and counting) drives straight from Japan.

There are items which we know will deteriorate - like belts. But that's trivial to recalibrate after replacement. Other aspects, such as the head alignment is much less susceptible to that same aging.

I always have to recalibrate the head alignment to get the best and most consistent signal strength. As a result, I actually believe my premium alignment is better than new.


Im on mobile so it's difficult to find, but there's a photo of a woman making FDS disks. I suspect those drives were calibrated better than that generic 10% margin of error. Why? OEM disks are within a more consistent and predictable read strength (after calibrating a drive).

P

I see, so you do touch the head screw that some people says to avoid.

But how do you know that you are within the 10% margin of error? Do you use a caliper, just trial and error by testing tons of disks or something else entirely?

Stephen

July 26, 2022, 04:55:37 pm #8 Last Edit: July 26, 2022, 05:02:51 pm by Stephen
There are a few indicators available...

Without additional tools:
  • The head should always be a set distance from the center of the spindle when it's in the "reset" position (top most position).

With additional tools:
  • The Peak-to-peak distance will be widest on the best read position (oscilloscope).
  • The standard deviation of the gaps and delays will be most consistent when the head is in the optimal position. This is easiest to obtain with an FDS stick but it's also possible to capture the read output directly from the op-amp with a logic analyzer and then process it as a CSV (e.g., excel, google sheets) or make software to do this.

I'm (slowly) working on public information to do this at home without tools by measuring the spindle RPM (using a phone-app stroboscope) and by measuring the distance from center of the spindle. A lot of people talk about the recommended gap of the head adjustment but ultimately it's the distance from the center of the spindle which is being adjusted.

I've updated my prices given the minimal demand. Ultimately, my goal is to make games and disk readers available for anyone who already has them. I will also be making pre-calibrated FDS drives available in the coming weeks. They're a pain to ship from Japan so I don't anticipate I will have more available after this initial lot is done (though I do really enjoy calibrating them).

P

I see, oscilloscope and FDSStick or logic analyzer, that sounds a lot better than just trying a bunch of disks until they seem to load.

We've recently been discussing this matter in another thread, and part of the conclusion was that the typical repair methods people use where they just keep adjusting in microscopic steps until a disk loads doesn't give you any way to know how close you are to the sweet spot, and is a cause for bad disks being written that only works on the poorly serviced drive it was written on, and even if it loads on some other drives, other poorly serviced drives that are too far off in the other direction can't load it.

Stephen

Quote from: P on July 28, 2022, 04:33:51 pmI see, oscilloscope and FDSStick or logic analyzer, that sounds a lot better than just trying a bunch of disks until they seem to load.

We've recently been discussing this matter in another thread, and part of the conclusion was that the typical repair methods people use where they just keep adjusting in microscopic steps until a disk loads doesn't give you any way to know how close you are to the sweet spot, and is a cause for bad disks being written that only works on the poorly serviced drive it was written on, and even if it loads on some other drives, other poorly serviced drives that are too far off in the other direction can't load it.
Disks written on a properly calibrated drive will be virtually identical to disk kiosk games.

I say virtually because a lot of the popular new tools don't cover the entire disk image when writing. Disks copied with a tool like disk hacker can be nearly undetectable.

2A03

I want to vouch for Stephen's services, I recently sent him three drives (from my standalone FDS and two Twin Famis) for servicing and they all came back in fully working order! He kept me informed every step of the way and the cost was extremely reasonable for the workmanship involved.

Salduchi

This is great! I will definitely keep this in mind!