According to ST schematics, there should be a header for almost exactly that purpose (maybe it's just soldered pads) - all you need to do is to disconnect (desolder) that header (shoould be located after the filters), cut one trace, and connect the switch. If the board doesn't have such header, you can always switch DS0/DS1 at filter location. Only 6 pins to desolder there, and you protect YM from switching surprises (if you keep the filters).
When marking holes in light colored plastic with a pen for drilling it is sometimes possible to see the inside mark on the outside by pressing a flashlight up to the plastic, that way you can mark and drill from the outside if it's a bit too tight for the drill inside or if you need some idea of where the hole is going to be on the outside.
with your mod does the internal drive operate at the same time as the external drive? Doing the D0 D1 flip does not seem to stop the motor signals going to both when using the external drive as the boot drive.
According to ST schematics, there should be a header for almost exactly that purpose (maybe it's just soldered pads) - all you need to do is to disconnect (desolder) that header (shoould be located after the filters), cut one trace, and connect the switch. If the board doesn't have such header, you can always switch DS0/DS1 at filter location. Only 6 pins to desolder there, and you protect YM from switching surprises (if you keep the filters).
Thanks for the info. I will check it in more detail. Maybe for my next stereo mod. 🙂
Excellent work. I love the desoldering kit you have. Thanks for sharing.
Interesting approach with the two sockets!
Really, excellent work and video. Extremely clean job. This mod is a must-have.
Thank you!
When marking holes in light colored plastic with a pen for drilling it is sometimes possible to see the inside mark on the outside by pressing a flashlight up to the plastic, that way you can mark and drill from the outside if it's a bit too tight for the drill inside or if you need some idea of where the hole is going to be on the outside.
That's good tip! Thank you.
Very well made video, thank you that's a nice mod !
with your mod does the internal drive operate at the same time as the external drive? Doing the D0 D1 flip does not seem to stop the motor signals going to both when using the external drive as the boot drive.
Does it? I haven't noticed.. It's technically not my mod. It's been around for decades.
😮
are there schematics available for this mod?
I did not draw a schematics. But I found this on google images: circuit-board.de/forum/index.php/Attachment/114193-DriveSwapAtariST-gif/
not so much schematics, but the service manuals are linked here. backofficeshow.com/projectsview#/atari-st-service-manuals/
I'll beat you at IK+ whenever you want...