Category: English
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(Failed) Pea whistle experiment
Well, not really failed, since every result is a result. I just found a way how this does not work. Two in fact. Okay, what’s this about? Oona Räisänen challenged her readers to construct a whistle that could transmit data using FSK. So, I thought about replacing the pea in a pea whistle with a…
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ATX computer power supply current limit.
(This post is also available in Dutch) For another project I’m tinkering with an old computer power supply. While I’m at it, why not see if I can build some crude current limiting. It does not need to regulate the current neatly, as long as it is short circuit proof. A LED on the 12V…
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Some short notes on the Lecroy9450 repair project
Because there is no big news yet, some short updates. – Claude Schwarz pointed me to the Yahoo user group “Lecroy Owners group”, they have design files for a HHZ406 replacement. (Made by Dieter Frieauff). So maybe the ext. trigger input can be repaired as well. – A service manual for this ‘scope (And others)…
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LeCroy 9450 oscilloscope repair
This was supposed to be an easy repair, and therefore not worth blogging about. But as it turns out, it might get interesting after all. (The ‘scope is not repaired yet) The “Leidse Makerspace” owns a LeCroy 9450 350Mhz DSO. When they moved to their new location I temporarily got this oscilloscope. Not just for…
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Quick and dirty Arduino optical mouse sensor experiment (a2620 chip)
I wanted to experiment with a optical mouse sensor, did a websearch, found this blogpost, and adapted the code for my A2620 mouse sensor. As it might be useful to others, below is my Arduino sketch and the processing sketch. Use the processing sketch to view the image from the sensor, or use a terminal…
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Fixing a broken SD card slot.
Repair companies are completely right they don’t repair on this level of detail, but swap an entire board instead. Much easy-er. But I don’t have spare boards lying around and I like a challenge, so… A friend of mine had a defective digital camera, someone forced the sd card in the wrong way, with bent…