25W 1% resistor shunted across the 811K to trim it to 800K again. 25W 1% resistor to be shunted across the 141.2K to pull it back to 140K and likewise a 50M. These 2 were mission critical in that case, so set about trying to resolve them and, seeing as the values had drifted upwards, it meant that I could tack on some smaller wattage resistors in parallel to "trim them back into spec" and it works out that I need a 20M. They however suggest a stockist that may have some other required values and the only one that they could with was the 140K but with a MOQ of 5 and after the P&P and VAT was added it would have come to £42, so thanks but no thanks FFS, I only paid £15 for meter Yesterday I revisited the project and did some calculations and the worst 2 resistors, 140K and 800K were also still in play on the other 3 upper voltage ranges so any errors on those first 2 would be multiplied on the higher voltage readings. ![]() ![]() Nothing doing, some were not being made any more and the 800K was a complete special and made in lots of 1,000 to order, err no thanks. ![]() Quick update, traced the original manufacturers of these resistors and had a chat with them about replacements.
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