Recently I got my first (dead) QL. I repaired it and got it working, but the unit had no microdrive. I investigated a bit about the replacements and I didn't liked none of them because as far as I know all are dessigned to be external, and are really expensive, so I have designed my own replacement
The thing looks like this:
It is based on the Raspberry Pico, thanks to the PIO units reproducing the internals of a microdrive has been somewhat easy. The thing is cheap, you can build one for around 20-30€ and that is taking into account all the connectors (I used a ribbon cable with male pin connectors instead of the stained wires that the original microdrives use) and the PCB.
Also, something that I wanted was in some way to preserve the feeling of the "cartridge", the device uses an edge female connector and then I designed a "cartridge" that contains an SD card, some buttons and an I2C screen, so you connect the cartridge and select the image you want to load. This also makes a lot easier to manage the images, as far as I know the other drives need to be connected to a PC to send/manage the images, this uses a standard FAT32 SD card so is a lot easier.
With a single "cartridge" you can manage two drives, the image is loaded into the pico's memory so the cartridge can be removed once it has been loaded, put the cartridge in a second unit and repeat the same operation. If you modify the content of a microdrive then you can reconnect the cartridge, it will rearm the image and then pressing a button it will be persisted in the SD card.
I have published all the work in Github: https://github.com/gusmanb/micropicodrive
The documentation is right now non-existent as I'm still finishing it, I need to adjust a bit the PCB's (I need to displace a bit the screw holes and the connector to make it fit at the center of the cartridge hole) and test the drive with Minerva (I have read that Minerva is a bit picky with "perfect" microdrives and unless there are some corrupt sectors it rejects the format, so I need to get a Minerva ROM and try it).
In any case all is there, the PCB's in KiKad format, the Pico firmware and more, if anyone wants to assemble one please feel free to contact me and I will solve any doubt about the device
Also, something else I have created is a replacement for mdvtools, I have created a .net version mith more functions, a GUI (but a console one, in the stile of Norton commander
) and is fully portable to Windows, Linux and MacOS.
Again, this is a work in progress and there is no documentation, so if anyone wants to try it you can download the source code (it is in the same repo) or just ping me and request a compiled version for your OS.
Cheers!
