Suggestions for an Amiga Floppy Drive that does not read disks properly.

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[This is a suggested approach to a non-working drive, please use your own knowledge and abilities, if this article seems inadequate]

"All I see is the Kickstart screen when I try to boot Workbench"

The floppy disk has a limited lifespan, the 5.25-inch floppies for the Tandy TRS-80 (Model 1 Level II, circa 1978) computer were said to not last longer than 1 year before becoming unusable. Prolonged storage in a moisture proof container in a cool location works to prevent damage to your disks from heat and moisture. Mold is an issue that arises with disks stored in warm and moist conditions, allowing the floppy disk platter to grow invisible to green/white particles. While degradation of the plastic platter from heat and age can’t be reversed, the disk might be cleaned of mold so that it works again, or not (3D printed devices exist for this).

Most Common Issue
Vintage floppy drives have issues where dust collects on the floppy drive heads, making its removal a constant issue. While a "Cleaner Disk” can do this with a bit of alcohol, actually opening your Amiga and removing the floppy drive, allows you to clean the heads by lifting the drive’s top cover off and with the use of a Q-tip swab dipped in alcohol. This is also an opportunity to blow out any other dust, to re-grease the worm-like spindle, and to oil the sliding rod at the base. Cleaning and lubricating a floppy drive may be all that is needed to bring it back to life.

Diagnosis
The quickest way to diagnose a problematic, but clean, drive is with a disk called "Amiga Test Kit" (ATK) that might be able to load from the original drive, or failing that, from a second working drive. An issue becomes loading that floppy into memory if you are stuck with OS 1.3, as it has no way to boot from an external drive without a "Boot Selector”. The one recommended uses an actual switch, is less than €10, $10 or £10, and allows “live” switching. Those switches that “Soft Select,” require a reboot that wipes out the loaded Amiga Test Kit. The external floppy drive may be a mechanical one, or better yet, a Gotek.

The risky method – hint: not recommended -- for loading the Amiga Test Kit program, is to load it using a working drive, unplug the drive’s power cord, then unplug the data cable; next, plug the bad drive into the data cable, and then carefully the power cable. If the computer is still functioning -- (you haven’t shorted a power supply, capacitor, blown a fuse or a CIA) -- then use the program to test your drive.

An Amiga user, dealing with 30-year-old devices, should consider having an external Gotek available. The Gotek can also replace the internal drive for other uses than drive diagnosis (such as loading multi-disk programs), by switching cables with DF0:.

Gotek Drives
These consist of a Gotek drive that has been modified with Kier Fraser's firmware, FlashFloppy, and an external floppy cable for this purpose. This external cable found was to be the Least Expensive through a series of searches. The Gotek’s main component, the AT32F415 Cortex-M4 MCU, is functional, but the AT32F435 is recommended by Kier for reasons on his FlashFloppy GitHub. Cheaply sourced from China (in the €20, £20,$20 range), a Gotek has many upsides, with the only downside being building yours inexpensively. They can be found for sale with an Organic text LED, rotary knob, and buzzer (if desired) on many sites for a wee bit more ~ 50% to 100% above the cost of parts.

Electronics
In addition, the vintage capacitors and resistors on these floppy drives may quit working and need to be replaced. The hint here is that the drive seems dead or partially dead, i.e., no clicks, no spinning, and/or no head movement. Glen at CRG has this [ Show youtube player ] showing his repair. Essentially, replace all the capacitors and check the resistors for their proper values, or barring that, look for black scorch marks at the soldered resistor ends.

Alignment
Disk drives go out of alignment with time and use. Most use an optical sensor (adjusted with a tiny screw “locked” in place with a drop of acrylic paint or epoxy); the drive will return to the optical sensor to facilitate its home position, track 0. Many YT authors have repair videos for this problem. If one uses the Amiga Test Kit disk alignment subprogram (that searches for 11 of 11 sectors read) while adjusting the sensor screw, one can re-align the drive (sometimes). The gold standard for alignment is an [ Show youtube player ] and an Alignment Disk, as this is how the drives were aligned at the factory.

Multiple sites have alignment information, for example, and several use XCopy for alignment, as it also shows the same information as the alignment segment of ATK. DuckDuckGo is your friend, and can lead you way beyond this page.

Drive Failure and Replacement
Thirty-year-old devices break, sad, but true. Replacement Amiga floppy disk drives, can be located on Amibay or auctions sites, but are also just as old and can be expensive. However, Sony only quit making the 3.5 in floppy in 2011, so there are likely PC floppy drives available that are less than 15 years old, perhaps some still new in the box. These can be modified in two ways to work with an Amiga: with the use of an adapter, or a DIY project -- Jan Beta has a [ Show youtube player ] available. Many users follow the instructions on the Jope.fi website and use Samsung and Sony drives due to their availability, and 3D print files for the A500 and A1200 eject buttons, as the different computer cases (A500/A1200) need different sizes. Most types of PC floppy drives need 1 cm of the front-top cover trimmed away to fit inside the respective cases.

Also Useful
There are PC floppy drives adapted to read & write Amiga disks using a PC, these include the DrawBridge (an Arduino board based interface that is inexpensive and an easy build), and the GreaseWeazle board, that, for example, can be purchased from several places. You’ll need a floppy power & floppy drive cable and a working, standard PC 3.5-inch drive. This is a good way to make a floppy disk containing Amiga Test Kit from the Web.

My Amiga drive clicks every second or so
In this case the drive may be fine, if not it is likely out of alignment. The Amiga drive checks to see if there is a disk in the drive by performing a quick check that results in a click. This means two things, the first is that the Amiga is functioning normally, and the drive “thinks” that it is; the second issue is that this noise is damn annoying and the use of Dosprefs will stop it -- and set an asterisk “*” as the default wildcard instead of “#?” in searches. Placed in the WBStartup folder, it may take a minute to kick in.

** An alternative to the Boot Selector switch, is to purchase or “burn” a Kickstart 2.04 or higher ROM, replace the 1.3, and boot from an external drive.