You Know You Can Do That with a 555

Hardly a week goes by that we don’t post a project where at least one commenter will lament that the hacker could have just used a 555. [Peter Monta] clearly gets that point of view. For a 555 design contest, he created both digital logic gates and an op amp, all using 555 chips. We can’t quite imagine the post apocalyptic world where the only surviving electronic components are 555 chips, but if that day were to come, [Peter] is your guy.

Using the internal structure of the 555, [Peter] formed a basic logic gate, an inverter, latches, and more. …read more

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Tea for Two: A Tiny Tea Timer

The ATtiny85 microcontroller doesn’t have all that much of anything: 8 KB of flash, an 8-bit architecture, and only eight pins (three of which are taken up with power and reset duties). And that’s exactly what makes it a great fit for tiny little projects.

[Mimile]’s Tea Timer has a switch, a button, eight LEDs, and a buzzer. Flip the switch to “set” and button presses run through the desired steeping times. Flip it to “run” and you’re timing. The LEDs blink and the buzzer plays “Tea for Two” in squawky square waves. Wonderful!

But wait, how to control all …read more

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Characterizing A Cheap 500MHz Counter Module

An exciting development over the last few years has been the arrival of extremely cheap instrumentation modules easily bought online and usually shipped from China. Some of them have extremely impressive paper specifications for their price, and it was one of these that caught the eye of [Carol Milazzo, KP4MD]. A frequency counter for under $14 on your favourite online retailer, and with a claimed range of 500 MHz. That could be a useful instrument in its own right, and with a range that significantly exceeds the capabilities of much more expensive bench test equipment from not so long ago. …read more

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