How a Marktplaats find sparks doubt about accuracy. Background I recently found two vintage Bleeker precision resistors on Marktplaats: a 0.1 Ω ±0.01% and a 0.01 Ω ±0.01% model. After some hesitation I bought them: to me, Bleeker is a long-gone pinnacle of Dutch engineering. A tolerance of ±0.01% is the same as ±100 ppm.…