Category Archives: Repair

Repair of malfunctioning equipment

Fluke 87 Fusible Resistor

Properly-designed multimeters that are suitable for professional and trade use have a number of components, usually near their input jacks, that are for the sole purpose of protecting both the user and (secondarily) the multimeter itself from over-voltage and over-current … Continue reading

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Fluke Banana Jack Repair

Ever bought a set of those cheap Chinese-made multimeter probes?  They probably had some little plastic inserts in the banana plugs.  For what reason I’m not sure, maybe to keep the safety shroud around the plug from deforming.  Don’t toss … Continue reading

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Beckman LCD Assembly Repair

The basic Beckman multimeter design that seems to apply to many of their 3½ digit models from the late 1970s onward include an LCD/processor chip assembly held together by various plastic parts that simply clip together.  The later Wavetek-branded models … Continue reading

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Fluke 23-III DMM Repair

The first two generations of the popular 70-series Fluke handheld DMMs included the 21 and 23 models, which were the same as the 75 and 77 respectively, except their cases were safety yellow instead of the usual dark gray.  The … Continue reading

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Beckman Industrial HD140 Multimeter

The HD140 digital multimeter from Beckman Industrial is another in the “heavy-duty” series, very similar to the HD110 in a previous article.  Unlike the HD110 however, this is a 20,000-count 4½ digit model with RMS-responding AC capability. Unfortunately I can … Continue reading

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HP 3468A Battery Replacement

The HP 3468A multimeter repaired in the last post uses something called “closed-case” or software calibration.  Instead of making physical adjustments to controls inside, calibration involves applying known reference levels and having the meter store calibration constants.  These are essentially … Continue reading

Posted in How-To, Repair | Tagged , | 16 Comments