Pop-art picture processing

A fun way to pep up black and white pictures is to modify the colors of the picture. For instance, take this iconic picture of Che Guevara. is is based on a black and white picture. I replaced white with red to to achieve the look of the well know version of this image.

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Famous version of the original picture taken by Alberto Korda

Replacing white with red is not the only option. Using the brightness a white or a black image for the RGB channels allows in total 64 variants to combine into a colored picture.

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EPROM data decay

EPROM short for Erasable Programmable Read-Only Memory is a relict from the early days of computing. It is a from of memory used to store program code for CPU and micro computer. As the name states it is a read-only memory this means that in normal operation the memory content can only be read but not altered. To erase then the memory the chip needs to be exposed to UV light. For this propose the housing of the chip has a built in quartz glass window. I used a so called flash gun which is basically a mains powered fast firing strobe light which is pointed on to the window.

The process of erasing the memory takes some time. I interrupted the erasing process to monitor the progress erasing process by dumping the chips memory into a file. During the first 60 seconds of the chip being exposed to the light no data change occurs. After that the memory fades pretty fast. Even the placement and structure of the memory cells on the chip is somewhat recognizable.

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Initial content

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Reading Flash and EPROM chips and visualizing their contents

This post can be seen as a follow up to my recent post[1] adressing the G540 universal programmer. The reason why I bought this programmer was that I have collected many old memory chips. I was always curious what kind of interesting data they might contain. A EPROM reader was needed and since my urge to build an Arduino shield for that purpose lapsed soon after sourcing some MCP23S17[2] SPI port expander chips.  So I bought the G540 I mentioned before.  Continue reading


  1. My first impression of the Genius G540 universal programmer 
  2. Microchip product page of the MCP23S17 

Genius G540 EPROM programmer: what’s inside and initial startup

Buying a G540 programmer

I have been collecting old EPROM chips for many years. Now I was curious what data these hold exactly. I am not looking for program data but more for character maps, hidden “Easter eggs” . Somehting like this Hack a day[1] post.

So I went to ebay an bought one of this widespread available “Genius G540[2]” EPROM programmers. Continue reading


  1. Hack a day on hidden photogrpahs in old Mac ROM chips  
  2. G540 programmer on ebay 

High Frequency device (Hochfrequenz-Gerät)

A few years ago I bought this interesting piece of medical equipment history. It is an induction coil with interchangeable gas filled glass electrodes. It was used “treat” all kinds of medical conditions. The handbook shows a large variety of uses this device could be used on, against and for. There are electrodes for your hair, eyeballs, vaginal electrodes and many even weirder ones. All the electrodes from the handbook are pictured at the end of the video.
I think it is a medical quack.
Nevertheless it is fun to show this thing at parties an zap people whit it.

I have the handbook scanned somewhere and will add it to this post any time soon. In the meantime here is a video of me presenting this thing.