82161A Digital Cassette with Audio Tapes?

[Les Bell]

Has anybody ever tried modifying audio dictation cassettes to work in the 82161A Digital Cassette Drive? I chanced to pick up some Phillips mini-cassettes from an office supply store, and they're mechanically near-identical to the HP digital cassettes, except for a notch cut in the opposite edge of the case to the heads opening. This aligns with a projecting tab in the drive recess, so that the digital cassettes will fit while the audio tapes won't.

Naturally, this has got me thinking. . . But before I do the experiment, I thought I'd ask if anyone else has done it first. I'm hoping that recently-manufactured high-quality audio tapes might be as good or better than aging salvaged digital tapes. The prudent course of action would be to cut a notch in one or two of the dictation tapes in order to test a) whether it works at all and b) the reliability. Only if results are good would I consider taking a scalpel to the drive itself.

Thoughts, everyone?