maxtherabbit wrote on 2023-04-27, 01:14:

Vipersan wrote on 2023-04-26, 23:16:

I guess this is pretty damned close as the good TEAC playing the floppy it formatted drops data above track 70.

That's not normal. You've got something wrong with the "good" setup if that's the case

I agree ...it could be the 'good' TEAC also has issues (doubtful as it has never been messed with)...or more likely the floppy I am using is sub par..
bit rot being a thing..
It isn't new sadly

You should calibrate to factory disks. Grab disks from various games from various companies.. write-protect them, and try to align to those. Don't trust other drives unless they've proven proper head alignment on factory disks too.

wbahnassi wrote on 2023-04-27, 10:19:

You should calibrate to factory disks. Grab disks from various games from various companies.. write-protect them, and try to align to those. Don't trust other drives unless they've proven proper head alignment on factory disks too.

Yes indeed..that makes sense to me..
Sadly I dont have many games floppies of the 5 1/4 type...
..and those I do have are 360k.
Ideally I'd need a 1.2mb commercial software diskette...
Do these even exist ?
certainly I have never handled one.
rgds

Vipersan wrote on 2023-04-27, 10:40:

Ideally I'd need a 1.2mb commercial software diskette...
Do these even exist ?

Yes of course they exist. Many early 90s software shipped on 1.2MB disks. Common ones include DOS 4 & 5, Might & Magic 3, King's Quest 5, Space Quest 4, Wing Commander 1 & 2,...etc.

wbahnassi wrote on 2023-04-27, 11:35:

Vipersan wrote on 2023-04-27, 10:40:

Ideally I'd need a 1.2mb commercial software diskette...
Do these even exist ?

Yes of course they exist. Many early 90s software shipped on 1.2MB disks. Common ones include DOS 4 & 5, Might & Magic 3, King's Quest 5, Space Quest 4, Wing Commander 1 & 2,...etc.

Thanx for the info..
I'll start searching for those titles.
cheers.

Ouch...
certainly pricey...and worse..non are up for grabs in the UK...so premium postage on top.
Anyone in the uk have anything they want to part with ?
It doesn't have to be a collectible ...just 1.2mb 5 1/4 ....not a copy and in good condition.
rgds

Floppy drives can be recalibrated with known good floppies and a scope. IMD is helpful but will never be enough on its own - yes, floppies will read OK but writes will miss the track a bit, and that affects also the existing data due to the way writing data works. "Good floppies" are for example software distros from the '90 - but it's best to test at least 2-3 of those with a scope, never assume any single disk is perfect.

Greaseweazle or kryoflux is required to properly dump or duplicate floppies with weird copy protection, but even those tools are not enough to re-create alignment disks. For that you also need a perfectly aligned drive (so chicken/egg problem) and also possibly microstepping to create data between usual tracks. That being said raw flux reads are the best thing we can do with common floppy drive hardware, and the resulting files are not so big (esp. when compressed) that we couldn't store the images in this format for future use.

The whole "disk modified" thing that kryoflux does is a bit bullsh*t quite frankly. Yes, detecting MFM stream breaks is a good sign sectors were written to after formatting but some software was duplicated that way - using diskcopy-like method rather then low-level flux write on proffesional duplicating machines. This will show as modified where in fact the floppy is not - so in the end you need to know and understand what the tool does and reports, not just consider it black magick and trust it to know better.
And speaking of, I can replicate a floppy, even one originally showing as modified, with Greaseweazle in such a way it'll show as untouched now. Yet another reason not to blindly trust such reports from dumping software.

As for the TEAC drives and their issues, make sure the 0 track sensor is not dirty and that the head moves smoothly. If the sliding rails bind (because of dirt) the seeks will end up in wrong places. Do not lubricate those - that's a quick fix (and hardly even that) not a proper repair of the problem. Such drives need to properly disassembled, cleaned and then recalibrated (if the sensor or stepper motor was moved, or the head carrier was completly detached from the motor).

Deunan wrote on 2023-04-27, 11:54:

Floppy drives can be recalibrated with known good floppies and a scope. IMD is helpful but will never be enough on its own - yes […]
Show full quote

Floppy drives can be recalibrated with known good floppies and a scope. IMD is helpful but will never be enough on its own - yes, floppies will read OK but writes will miss the track a bit, and that affects also the existing data due to the way writing data works. "Good floppies" are for example software distros from the '90 - but it's best to test at least 2-3 of those with a scope, never assume any single disk is perfect.

Greaseweazle or kryoflux is required to properly dump or duplicate floppies with weird copy protection, but even those tools are not enough to re-create alignment disks. For that you also need a perfectly aligned drive (so chicken/egg problem) and also possibly microstepping to create data between usual tracks. That being said raw flux reads are the best thing we can do with common floppy drive hardware, and the resulting files are not so big (esp. when compressed) that we couldn't store the images in this format for future use.

The whole "disk modified" thing that kryoflux does is a bit bullsh*t quite frankly. Yes, detecting MFM stream breaks is a good sign sectors were written to after formatting but some software was duplicated that way - using diskcopy-like method rather then low-level flux write on proffesional duplicating machines. This will show as modified where in fact the floppy is not - so in the end you need to know and understand what the tool does and reports, not just consider it black magick and trust it to know better.
And speaking of, I can replicate a floppy, even one originally showing as modified, with Greaseweazle in such a way it'll show as untouched now. Yet another reason not to blindly trust such reports from dumping software.

As for the TEAC drives and their issues, make sure the 0 track sensor is not dirty and that the head moves smoothly. If the sliding rails bind (because of dirt) the seeks will end up in wrong places. Do not lubricate those - that's a quick fix (and hardly even that) not a proper repair of the problem. Such drives need to properly disassembled, cleaned and then recalibrated (if the sensor or stepper motor was moved, or the head carrier was completly detached from the motor).

Thanx for the advice/info..
All information is good information.

FWIW I'm claiming the TEAC aligned to the best of my ability now.
Using IMD with audio beeps so I dont have to watch the monitor whist doing head alignment.
I first found a very good HD 1.2mb disk with as few bad clusters as possible 5 to be exact...
Formatted this on the Canon 5501 slim drive I recently removed from my Compaq portable III (286)
This drive has never been messed with and likely had very limited use.
Ran a floppy cleaning disk through it first then formatted the Good Dysan HD 1.2mb disk.
This disk I then used to align the TEAC.
Which now gives excellent amplitude and accuracy over all tracks and heads..
0/1 ..tracks zero to 79
I'd still like to test it with some factory software on a 1.2mb disk..but not having anything suitable..this seems the best solution I can come up with.

In the end I had to introduce more variables..
The only constant being the lower head in relation to the metal strap connecting head sled to stepper motor.
..and yes even the stepper motor had been moved.
So..in conclusion.
The upper head had been moved relative to the lower head..
The stepper motor had been moved relative to the 2 locking screws on the chassis..
The pcb carrying the zero track sensor had been moved relative to the plastic shutter attached to the head sled...underside.
Not a job I want to repeat in a hurry...but thats what you get for buying a cheap non working 5 1/4 inch floppy drive from fleabay.
I have learned a lot and feel confident I could align another...thanks to IMD and grey matter logic....and a helluva lot of patience.
rgds