Recently, I’ve soaked my EXT250 turbomolecular pump in rotary vane forevacuum pump oil by not following the proper shutdown procedure. In this note I describe my attempt at repairing it.Read on →
Today, I decided to finally plug in my instruments properly, and plugged both my cheap lab PSU (ARKSEN 303D) and oscilloscope into sockets on the same strip with real ground prongs. After connecting the scope ground with the PSU negative rail, it quickly became clear that something’s wrong, because the wire connecting them went white-hot and sort of caught fire.Read on →
In this note I will describe a part of a 50W resonant LC converter that I am designing. The converter will be modular: it will feature a control board with an Ethernet interface, a frontend board with a rectifier/multiplier and a matching network to allow current/voltage readouts, and a power board with the high-voltage transformer, its driver and signal isolation.
This note describes the first revision of the power board.Read on →
After assembling a full-wave rectifier out of some 1A7 1kV-rated diodes, I noticed that it does not, in fact, rectify. I speculated that the diodes I used have a recovery time too high. Since it was not specified in the datasheet, I decided to measure it myself, which I describe in this note.Read on →
In this note I describe an improvised vacuum chamber made out of stuff I had laying around the house, and some fun things I did with it.Read on →
I broke a Nokia 3310 display, and in a closeup, both pixels and what appears to be segment electrodes at the border, are distinctive.Read on →
In this note I describe a simple and convenient arrangement of an E12 resistor set that, crucially, takes very little space.Read on →