A revamp of the Apple II Disk II Analog board and the Motor Control board have been in the works for the past several years. Now that work has come to fruition and the new ReAnalog and Motor Control boards are available through Chris Torrence’s CT6502.ORG website.
About the boards
The ReAnalog Card is a recreation of the original Apple Disk ][ Analog card from 1978, using modern components and a printed circuit board. This allows the sensitive magnetic signal from the read/write head, as well as the power supply, a much better and noise-free environment than its original counterpart. The designer has strived to keep the design as clean as possible using surface mount components, keeping the backside totally clean and even. The board does, however, retain the original MC3470 read amplifier which is a through-hole component. The reason is that after many tests, this part still outperforms other setups without it.
The board features a 3-way write protect jumper:
- NORMAL: write protection is defined by the notch being covered or not on the disk itself.
- Write Enabled: you can always write to the disk, even if the disk is not notched. No more hacking your drive or drilling holes to install a switch!
- Write Disabled: you can never write to a disk, even if it is notched.
The board also has two potentiometers which precisely tune the MC3470 chip for best performance in an Apple II and are best left untouched. Modify them at your own risk. For customers who will use the ReAnalog card exclusively to image disks with hardware such as the Applesauce FDC, there are procedures to significantly improve the imaging performance. Please contact ‘kkr75’ or ‘rikkles’ on the Applesauce Discord server for more details.
The Motor Control Board
The Motor Control Board is a recreation of the original Apple Disk ][ Motor Control Board from 1978, using modern components. Although the original Sony CX065B controller integrated chip was retained, the board provides a much sleeker and cleaner layout than its counterpart, and uses a terminal block as a quick disconnect, which does not alter connection reliability in any way. The potentiometer has been precisely tuned for a motor speed of 300RPM, although this may need some refinement on your particular drive.
Installation
The video below shows detailed installation instructions. You will need the following tools: A Philipps screwdriver, wire cutters, and either a small pair of wire strippers or a sharp hobby knife. Although the installation is straightforward, it still requires a minimum level of skill including cutting and stripping wires. You do not need to do any soldering or desoldering unless you specifically wish to avoid cutting the motor wires. If you have any doubts about your skills, please watch the video thoroughly before purchasing.
Purchasing
The ReAnalog and Motor Control board for the Apple II Disk II floppy drive are available as a set for $195 plus shipping and taxes. They can be purchased at the following URL: https://ct6502.org/product/disk-ii-refit-kit/
