As far as I know, DEC was the only vendor to do this.
Chuck, Also my
DATAPOINT 1800 uses this RX02 pre format.
Sadly they only made a initialize and DOSGEN software to transfer a RX01 to a RX02 mixed type floppy.
Never a Format. I know this from the developers them selves.So have to use Pre-Format RX02.
The 1800 it self can not read RX01 type, there should be software, I have not.
C.10.2 Size of a diskette (Datapoint 1800)
there are 77 tracks each contains 13 256 byte sectors (physically 26 128 byte sectors).
First track is not used to help provide compatibility with IBM equipment, additionally the logical last sector on each track (sector 12 counts from 0) is not used by DOS.C
RQDX3 I manage to build in to my PDP1123 with 2x ST225's
RX33 I used a TEAC FD-55GFR, just fiddle with the jumpers.
Can't find at the moment the info to build, but Line-Time-Clock and 18/22 Bit can be done at the back plane PDP11/23.
The build, Its in Dutch but pict's will tell enough.
http://www.transistorforum.nl/forum/index.php?id=48087
As to use RX01 with RQDX3 may me look into the Imagedisk Software?
That uses a 1,2MB settings also and can convert to 77 track SD (RX01).
As in a PC a 1,2MB drive can read/write a 360k disk, should PDP11 also I think read RX01 in RX02 mode.
The RX02 drive it self you have to physical strap it to RX01 but may be with RQDX3
and a software convert like they did with Imagedisk you could think of that.
May be just an address redirect from RX02 to RX33 in the RT11 software?
So PDP thinks it is talking to RX02 controller but in fact its the RQDX3?
Info:
Digital Equipment Corp. RX01 [7]
SS/SD, soft sectored 77 tracks, 26 sectors per track, 2002 sectors per diskette, 128 bytes per sector
capacity 256,256 bytes
48 tracks per inch
bit density 3200 bits/inch at inner track