We have positive identification! we do have an A01 variant of the IBM
3430, so it is functional as a standalone unit.
We were sent a snippet of an IBM parts catalogue (thanks to Herman
from The Netherlands) for the 3430 and it clearly shows the
differences between A01 and B01 units:
1. The most obvious indication(!) is the front-panel on the top-right
of the unit. The A01 has 6 switches and several extra indicator
lights, whereas the B01 has just 4 switches and fewer lights. We will
get some pictures onto the gallery that will make this description
easier to interpret - the A01 operator panel appearance is busy, the
B01 operator panel appears minimalist.
2. As has been noted in this thread, the 3430 is a bus/tag peripheral.
As it happens the B01 variants are connected via specific flat white
ribbon cables to allow reduced/simpler cabling - this is highlighted
in the 3430 brochure as a positive selling point since underfloor
cabling was not required for the additional B01 units. Only the A01
has the bulky bus/tag sockets to connect to the host system.
3. The last picture in our picture gallery showing the large box of
circuit cards (that incidentally has two prominent fans mounted
directly on top - they are quite noticeable when you remove the main
front cover) - this is only fitted to the A01 and holds the controller
electronics shared among the entire daisy-chain of tape drives. This
space is empty on the B01 as it relies on the controller from the A01.
On opening a B01 someone would be struck by how empty the space under
the tape drive appears.
Once these differences are known then it explains why there are no
designations on the unit, it is quite easy to tell them apart with