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    PCB Transfers

    Hi All, I'm looking for a cheap and easy way to transfer my circuit onto copper board. I'm using a piece of software that can print the tracks 1:1 on a printer. I'm aware of the various methods out there, photoboard+UV light, transfers, laser printer/toner method, etch-pen, etc. I came across a...
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    Phototransistor Information

    Hi, I'm using a phototransistor ( SFH300-3 ) in my circuit that has rise/fall times of around 10uS. I need a phototransistor that will respond to 2uS or quicker pulses of light. When the manufacturer specifies a rise time for example, does this mean that the phototransistor has to be illuminated...
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    LM2917N F-V converter IC

    Hi All, I've almost finished my project for a tachometer circuit. Testing went well until I appear to have hit upon a snag for which I need some help. It concerns the LM2917N frequency to voltage converter IC, which I can happily 'program' to give the correct output with a given frequency input...
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    Comparator usage.. Help!

    Hi All, I've got a small project on the go and need some advice. It concerns the use of voltage comparators, in particular the LM311 and LM393. I've got a breadboarded ( plywood and cup screws!! ) test setup and I've managed to get both comparators to work including some hysteresis, but I am...
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