Archive for April 2017

HP 7044A X-Y Recorder Teardown, Lorenz Attractor

I picked up an HP 7044A X-Y recorder on eBay recently. This one was made in the early 1980’s and by today’s technology standard it is rather ancient. And because of this, it is very easy to interface with as the input is completely analog. My plan was to do some experiments down the road using the X-Y movements capability of this HP recorder. Continue reading ‘HP 7044A X-Y Recorder Teardown, Lorenz Attractor’ »

Cheap UV EPROM Eraser Teardown and Spectrum Analysis

Till recently, I have been using custom circuitry whenever I needed to backup some firmware. But the process was rather tedious as for each kind of EPROM or EEPROM I needed to study the protocol and timing requirements and then come up with the required circuitry on a breadboard. And wiring can easily become an issue with a high pin-count chip. So I finally got myself a proper EPROM programmer (it’s a TL866A) along with a $15 generic UV EPROM eraser so I could program EPROM/EEPROM’s quickly. While it was fun to build a programmer circuit each time, I think the effort can be put into something more useful. Continue reading ‘Cheap UV EPROM Eraser Teardown and Spectrum Analysis’ »