no, you cant do that
 an RA81 is an SDI disk, the RQDX3 is an MFM controller. 
You need something like a kda50. 

isildur

On Thu, 1 Feb 2001, NetBSD Bob wrote:

> > Or use the RA81. More space, more noise, more power dissipation, much
> > more fun. ;-)
> 
> Will the RA81 run on the RQDX3?  Hmmm, if so, I gotta find one.  I got
> the halfrack, and a 9 track tape, and a BA23 sans plastic case, so
> that might make up a sort of rack VAX.... hmmmm.....
> 
> What all is needed to hook up an RA81 to an MVII.
> 
> Just thinking out loud.....
> 
> Bob
> 
> 
>