[William Dudley] picked up a Fluke 8840A bench multimeter at an public sale, however was once unhappy to determine that it was once studying resistances inaccurately. It was once additionally lacking the non-compulsory board to permit AC measurements. Wanting to make use of the in a different way beautiful meter, he set about repairing and upgrading the instrument.
Fortunately, the 8840A was once from a time when Fluke used to brazenly post schematics in its manuals. Thus, blended with having a look at some pictures on-line, it was once easy for [William] to recreate the unique AC “Possibility 09” board to permit the specified capability. As is most often the best way, his efforts didn’t paintings first time, however after some bodge wires have been put in, all was once nicely. [William] stories the measurements are “affordable, perhaps even enough” without a calibration undertaken.
Repairing the resistance factor was once simple. It became out to be corrosion at the selector switches, published when high-resistance measurements have been correct, however low-resistance measurements weren’t. A little of flick-flacker with some touch cleaner sprayed into the switches were given issues operating once more well.
It’s great to peer previous {hardware} restored to complete capability, in particular when it’s as sexy and well-built as an previous Fluke meter. Bringing again previous equipment from the useless? we wanna pay attention about it!