Little Joe never once gave it away

The manufacturers of inkjet printers are constantly looking for ways to make sure you pay and pay, no matter how much it depletes your wallet; in fact, they're even resorting to setting time bombs in the cartridges to make sure you have to buy new ones.

You might not think that such a scheme would be possible with an impact (read "dot-matrix") printer that runs off old-style spools of ribbon.

As we discovered today at 42nd and Treadmill, you would be wrong.

IBM's 6500-series printer is an impressive workhorse, but don't try to fool it with a generic ribbon: the spindle is just slightly too small, and there's a gizmo inside the head assembly that:

• tells you how much life the ribbon has left, based on some algorithm which you're not told;

• checks the spool for the presence of a barcode, and refuses to accept an off-brand ribbon no matter how clever your jury-rigging may be (and mine's close to legendary).
  

There is one way out — unroll all 200 feet or so and thread the contents of a generic ribbon onto IBM's spool — but this is messy and time-consuming. (Do not ask why I know this sort of thing.)

Posted at 6:25 PM to PEBKAC