Non-512-byte sector drive cloning?

[Eric Smith]

On Wed, Feb 11, 2015 at 3:48 PM, Roe Peterson <roeapeterson at gmail.com> wrote:
> What, actually, is the blocksize?  1024 or ?

I have no idea specifically about the SC40, but in general when a
PDP-10 (36-bit machine) when using byte-oriented media uses 576-byte
sectors, in order to store a PDP-10 128x36 block. That's what DEC did
on the HSC50/RA81.  (Note that you can only use an RA81 with a
factory-supplied 576-byte HDA; there's no way to field-reformat an
RA81 HDA to a different sector size due to the use of embedded servo.)