Printing labels on Epson TM-T88IV

Epson TM-T88 is a series of thermal receipt printers that are very common and can be found on eBay for as little as $10, as well as elsewhere around the world. It is not designed to print on self-adhesive labels but, given that it has a cutter, can be easily and reversibly adapted to doing so.

In this note I demonstrate how to reliably print labels on a TM-T88IV.

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Casting silicone using modeling clay pattern

I have tried hand-forming a pattern using modeling clay, cast an RTV silicone mold around it and then destructively extract the pattern by heating it in an oven.

This does not work: silicone conducts heat poorly, and the modeling clay, generally, tends to catch fire before it liquefies.

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Cleaning an Edwards EXT250 turbomolecular pump

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.

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Ground loop in a lab power supply

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.

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50W LC resonant converter, power board V1

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.

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Measuring diode recovery time

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.

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CNC-milling glass

In an earlier note I described an improvised vacuum chamber. I wanted to perform sputtering in it, but an acrylic flange would melt if the feedthroughs got hot enough (and they will get hot), and that would be pretty gross.

In this note I describe how I CNC-milled a glass flange.

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An improvised vacuum chamber

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.

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MOSFET-based Gouriet-Clapp capacitive three-point oscillator

In this note I describe a Gouriet-Clapp capacitive three-point oscillator, which is an extremely simple circuit that produces high-frequency (~20-30MHz) electromagnetic field. It can light up gas discharge tubes and as such can be used to estimate pressure in vacuum systems.

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Photographing PCD8544

I had a broken Nokia 3310 LCD on my hands, so I decided to take a photomicrograph of the display controller, PCD8544. As far as I’m aware this is the first publicly accessible die shot.

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