Building a Fake Printer to Grab Screenshots Off the Parallel Port

[Tom Verbeure] recently found himself lamenting the need to take screen grabs from an Advantest R3273 spectrum analyzer with a phone camera, as the older gear requires you to either …read more Continue reading Building a Fake Printer to Grab Screenshots Off the Parallel Port

Debugging Electronics: To Know Why It Didn’t Work, First Find What It Is Actually Doing

Congratulations, you have just finished assembling your electronics project. After checking for obvious problems you apply power and… it didn’t do what you wanted. They almost never work on the first try, and thus we step into the world of electronics debugging with Daniel Samarin as our guide at Hackaday …read more

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Getting a Handle on ESR with a Couple of DIY Meters

Got a bunch of questionable electrolytic caps sitting in your junk bin? Looking to recap a vintage radio chassis? Then you might need to measure the equivalent series resistance of the capacitors, in which case this simple five-transistor ESR meter might come in handy.

Even if you have no need for an ESR meter, [W2AEW]’s video below is a solid introduction to how ESR is determined. The circuit itself comes from EEVBlog forum user [Jay-Diddy_B] and is about as simple as such a circuit can get. Two transistors form an oscillator that generates a square wave that drives a resistor …read more

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