Famicom World

Family Computer => Buy / Sell / Trade => Topic started by: Stephen on June 27, 2022, 03:17:05 pm

Title: FDS Services (Calibration, Disk Refresh)
Post by: Stephen on June 27, 2022, 03:17:05 pm
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 (https://www.ebay.com/itm/234732339439))
Intended for general use with the Famicom Disk System Drive or Twin Famicom.

Premium - $75
Intended for use with the FDS Stick (e.g., backing up disks, refreshing disk images).


Additional Services:

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

Disk Refresh - $30
Perfect for your worn or out of calibration disks.

FDS Stick -> FDS Disk Drive Cable - $30
Tidy cabling available for use of FDS Stick and FDS Disk Drive.

FAQ:
Disk errors can still occur on calibrated disk drives. How?
How do you provide calibration (disk drives, disk refresh)?
What is the difference between "basic" and "premium" calibration?

Terms of Service
Title: Re: FDS Services (Calibration, Disk Refresh)
Post by: ericj on June 27, 2022, 06:47:45 pm
What's the difference between:

Basic Spindle Speed calibration
Basic Head Calibration

and

Premium Spindle Speed calibration
Premium Head calibration?
Title: Re: FDS Services (Calibration, Disk Refresh)
Post by: Stephen on June 27, 2022, 09:08:26 pm
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.
Title: Re: FDS Services (Calibration, Disk Refresh)
Post by: hgage2003 on June 29, 2022, 12:51:16 am
Can you make Ram Adapter to Twin Famicom cable?
Title: Re: FDS Services (Calibration, Disk Refresh)
Post by: Stephen on June 29, 2022, 08:24:31 am
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 (https://3dscapture.com/fdsstick/) (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.
Title: Re: FDS Services (Calibration, Disk Refresh)
Post by: P on June 29, 2022, 01:03:17 pm
So Premium is basically making it factory aligned so that it can write disks properly?
Title: Re: FDS Services (Calibration, Disk Refresh)
Post by: Stephen on June 29, 2022, 05:08:41 pm
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).
Title: Re: FDS Services (Calibration, Disk Refresh)
Post by: P on July 26, 2022, 04:49:24 pm
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?
Title: Re: FDS Services (Calibration, Disk Refresh)
Post by: Stephen on July 26, 2022, 04:55:37 pm
There are a few indicators available...

Without additional tools:

With additional tools:

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).
Title: Re: FDS Services (Calibration, Disk Refresh)
Post by: P on July 28, 2022, 04:33:51 pm
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 (https://www.famicomworld.com/forum/index.php?topic=15270.0), 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.
Title: Re: FDS Services (Calibration, Disk Refresh)
Post by: Stephen on July 28, 2022, 05:44:01 pm
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 (https://www.famicomworld.com/forum/index.php?topic=15270.0), 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.
Title: Re: FDS Services (Calibration, Disk Refresh)
Post by: 2A03 on August 05, 2022, 03:05:30 pm
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.
Title: Re: FDS Services (Calibration, Disk Refresh)
Post by: Salduchi on August 21, 2022, 01:51:28 pm
This is great! I will definitely keep this in mind!