{"id":1309,"date":"2017-01-22T15:18:00","date_gmt":"2017-01-22T14:18:00","guid":{"rendered":"http:\/\/www.daqq.eu\/?p=1309"},"modified":"2017-01-29T17:55:38","modified_gmt":"2017-01-29T16:55:38","slug":"l110-metra-blansko-resistance-decade-box","status":"publish","type":"post","link":"https:\/\/www.daqq.eu\/?p=1309","title":{"rendered":"L110 METRA Blansko resistance decade box"},"content":{"rendered":"

Recently I got a L110 resistance decade box made by METRA Blansko, in former Czechoslovakia. Unfortunately something was rattling inside, so I had a quick look inside to remove the offending part - it was a small metal nut that had fallen inside, probably during some previous disassembly.<\/p>\n

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Full view of the device<\/p><\/div>\n

The unit is specified as 0.1%, however, measuring the device revealed that several ranges were out of specification. The 10x and 100x are a little above spec (max error around 0.18), the 0.1x are off by a fair amount. The other ranges, particularly the x1000 and above are very accurate (max error of 0.04%). The device is fairly accurate, when considered that it's probably older than me \ud83d\ude42<\/p>\n

The multimeter (Agilent 34401A, checked against a regularly calibrated instrument) was nulled against the 0\u03a9 reading (when the device was set to 0\u03a9) and the resistance was measured by the 4 wire method.<\/p>\n

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Error plot<\/p><\/div>\n

While I had it opened, I took a few pictures. Enjoy.<\/p>\n