First progress report on a multi-channel magnetic drum inner ...

X-5
Number of heads required: 180 j tubas: about 500; power: 5 K»V;
physical dur.erisions of the magnetic unit alone: 1 ft. x 2 ft . x 2 ft.
Finally, it r;,ay be worthwhile to coajuent that when used strictly
as a reinory org.an in conjunction with a separate arithrietic unit, the
hypothetical iTiapnetic drum unit described above is grossly inefficient
in at least one sense. That is, the unit is capable of accomplishing
7
A. 5 X 10 useful f,ating and storing operations per second, but in such
service would in fact be called upon to execute only something like
one tenth of one per cent of this number during actual read-in and
read-out operations.