QIC 3M "Magnus 1.2" carts

[Chuck Guzis]

I have received a few of the above-mentioned DC300-sized QIC carts for
recovery.   The usual stuff about tension bands applies, but I'm a bit
stymied.

The official specs for these tapes say that they're SLR 3.  I've tried
Tandberg SLR 3, 4 and 5 drives (any of which should be able to read
these) with no luck.  I've even tried an SLR2 QIC525, though why someone
would pay for more tape than they need is a mystery.

These would be ca. 1990 and most likely on a Mac, although the latter is
pure conjecture.

Before I unspool some of this tape and have a look with developer, am I
missing something?

--Chuck