Vulcan Hard Disk Problem

[dons@TENET.EDU (Don Simmons)]

I just acquired Vulcan (Applied Engineering) 40 meg hard disk for wife's
Apple //e (an old one (1983) with black-faced floppies).  Installed unit,
checked out the software and loaded some files -- no problem.  Two days
later wife goes to access the system and the floppies won't read.  Access
light goes on, but there is a read error.  ProSel software on Vulcan
shows no path.

I troubleshoot (shooting in the dark - I've been away from Apples for six
or seven years) by disconnecting harddisk controller card and trying
to boot directly to good old Drive 1.  Tries to access, but no read.  Aha! 
Bad controller.  

Borrowed controller from another //e.  Put it in.  It created high
pitched whistle and would not even access.  Again, removed HD controller. 
Same high pitched wail with no access.  (It worked in the //e it was
removed from).

Wife is down (and not too happy).  She hasn't yet transferred her files to
the HD and can't use her floppies.  Result is there are many things I
can't do until problem is solved.  All help is gratefully received.

Thanks in advance.

Don Simmons
Fort Bend I.S.D.
Sugar Land, Texas
dons@tenet.edu