Sirius1/Victor 9000 - has anyone ever seen one working?

[Tony Duell]

> > This would seem to preclude using a standard floppy drive.
> 
> Depending on the range of speeds the Victor used, it might be possible
> to replace the motor control circuit on a standard floppy drive.

The floppy drives in my Sirius are Tandon TM100 _chassis_ with the 
standard heads. stepper, track 0 switch, write protect sensor, etc. IIRC 
there is no index sensor. I don't know how many TPI the drives are 
designed for, they are single head, but the control PCB is designed for 2 
heads per drive, so clearly a double-sided version was planned

There is no stnadard Tandon logic board. Instead there's a Sirius board 
on top of the deives. The little 0.1" molex connectors from the various 
drive components connect to this, there's a 50 way ribbon cable down to 
the mainboard, and a power connector.

AFAIK the spindle motor is the stnadard one, but obviously with some 
special control circuitry on the controller board (whcih includes an 8048 
microcontroller , a couple of 8 bit DACs ad a coupleof LM2917 tacho ICs.

The stepper motor driver circuitry seems to have been designed to use 
either 5 wire unipolar motors (Tandon) or 4 wire bipolar motors (MPI, 
Micropolis, etc). So unlike the Commodore drive units (Which this has 
some similarlites to, of course), it appears there aren't 2 versions of 
the controller board for different drives (the CBM 8050, for example, had 
2 versions of the analogue board to cater for different types of stepper 
motor). I don't know if there was a ROM change for different steppers on 
the Sirius, though.

To get back to the origianl comment, I see no problem in _repairing_ the 
original drives using Tandon parts. Said drives are very easy to work on, 
and the parts are common.

-tony