Recent content by ap2wf

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    Microscope capacitor exploded

    Hi. On the second picture the capacitor brand written is Rubycon, which is a Japanese brand of late 60s. The capacitor is oil filled and polarised. However, it should be of more priority and importance to confirm, whether you moved from 120 VAC to 220 VAC utility supply area, and also what is...
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    Microscope capacitor exploded

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    digital multimeter sinclair dm 450

    Repairing Sinclair DM 450 Hi... I have a few pictures of the Circuit Board. I took it out of the plastic box.
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    digital multimeter sinclair dm 450

    Thanks Olivier, I'll check thru ICL7103 and all ICs supplies, for this is what I wanted to do. All the ICs are socketed while LED display is mounted on a sub-assembly/PCB and directly soldered. There is no oxidation or rust but looks to be handled carefully for proper soldering temperature...
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    digital multimeter sinclair dm 450

    I checked the display section as advised, but no change. Can I check by providing input signal to ICL7103 A/D converter? How and what signal?
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    digital multimeter sinclair dm 450

    Sinclair DM450 Repairing Thanks Steve for your response. I may correct that Sinclair DM450 Digital Multimeter uses 7 segment LED modules, not LCD. The DS75494N as LED Display driver, MM74C48J BCD to 7 Segment Decoder, ICL7103ACPI A/D Converter, and a had full of Op-Amps and chips like CD4066BE...
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    digital multimeter sinclair dm 450

    Sinclair DM450 Repairing Can we exchange the photographs of the inside views, may be helpful for both of us? In the mean time we may get some senior's advice.
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    digital multimeter sinclair dm 450

    Sinclair DM450 Repairing. Hi, I am also in the same boat and am repairing Sinclair DM450. The meter is not totally dead but shows 1 at the left most digit. Also, the next digit flickers if I touch somewhere under the digit driver and BCD to 7 segment decoder ICs. No effect if test probes are...
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