For the Eagle Term II v1.9 Sourcecode I had to repair and recap a SFD-1001 drive.


A very common issue on these drives are leaking capacitors causing damage on the motor control PCB. These should be replaced as soon as possible.

A few important notes on the way:
1. The screws holding the rotor(magnet) and especially the PCB screws are ridiculously tight, it’s almost as they are not loosening up at all. Make sure to have an exact size screwdriver and use correct amount of force to unscrew them, you don’t want to end up with destroyed screw heads.
2. There is a fragile flat cable on the underside, be aware of it before lifting up the PCB.

 


Remove the three screws and lift the rotor(magnet).

 


Remove the four screws holding the PCB marked with red circles and remove the spacers (mine had three of them).

 


Desolder the two connectors marked with red squares.

 


Close up of the cable in the lower left corner, be careful desoldering it.

 


Drive motor control PCB.

 


Original capacitor values and sizes. h=height, d=diameter, r=lead spacing.

 


Component list and manufacturer part numbers, some caps are rated higher than the original voltage value. There is limited space for the capacitors but the components above will fit. Capacitors C13/C14/C15 are bipolar.

 


Part numbers for IEEE-488 Connectors also available from DigiKey.

 

 

SFD-1001 Head Resistance check.


Resistance RW1 or RW2 to CT : 37 ± 30% Ohms
Resistance ERASE to CT : 8.0 ± 30% Ohms
Information above from 8250LP SFD-1001 Disk Drive Technical Manual

 


Measurements from the field on working drives for reference.