Intermittent black squares printing from Pioneers to 82240B

[Dave Britten]

Seems like my 82240A is a lot more forgiving than the B. I just printed my solver library (at least a foot of printout) from a distance of about 3 inches, and don't see any obvious signs of missing characters. Whether this is something specific to the two units I happen to have, or which applies to the A and B models in general, I can't say. I'm suspicious that the power LED behind the filter on the B is causing some kind of interference (e.g. backscatter into the receptor). I might look at desoldering it and replacing it with a roughly equivalent resistor. Or maybe just wrap it with some electrical tape.