Category: Technology

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MOSFET Basics

I've seen a lot of questions recently on various forums involving MOSFET projects not working as expected.
I've been meaning to write up a quick summary of how to use them for simple microcontroller projects, so I figured this was a good time to do it.

automator-icon 1

F-Script Injection in Mavericks

I continue to use F-Script occasionally to investigate how programs work internally. The framework itself has been updated to handle the changes in OS X Mavericks. However, the developer tools included with Xcode 5 swap out the gdb debugger for lldb, breaking the injection script again. After playing around with the automator action some more, here's what I came up with that works on Mavericks.

This is the way I normally use gpredict.  It also shows the single-sat transponder view in the bottom right. 4

gpredict build for Mac

I really like the open-source satellite tracking program predict. I'm primarily a Mac user, so to get it I had to use macports to build it. I don't really care for alternate build systems like that, so to use it on my other systems, I decided to bundle it all up, and to spare some people the trouble, I'm going to post it here.

Schematic showing connection of transmitting and receiving components for the optically-isolated serial port. 1

Fluke Scopemeter 97 Screenshot Hack

While waiting for parts to arrive to build a proper optical serial interface, I really wanted to get some screenshots off of my oscilloscope. Knowing that the infrared LED in the interface is directly transmitting the serial signal, I figured I should be able to tap into that driving signal to obtain the serial information.

Screen illuminated by the newly-installed EL backlight. Success! 20

Fluke Scopemeter 97 EL Backlight Repair

I have a Fluke ScopeMeter 97 that's come in really handy over the years. Before I got it, it was a sales rep's demo unit, so it was used pretty hard. The screen backlight is an electroluminescent panel, and their intensity can fall off pretty dramatically over it's life. This particular display is also transflective, which makes it extremely readable under direct sunlight, but means the backlight is essential to using it in indoor lighting. To use it in the past, I'd shine a bright desk light on it, but I've always wished the backlight would just work.

The green capacitors toward the top have flat tops, as they should, while the black capacitors in the bottom half are showing signs of failure with their puffed tops. 0

Capacitor Plague (Part II)

In Part I, I discovered my monitor suffered from the capacitor plague. I ordered new capacitors to repair it and received them a few days later.

The green capacitors toward the top have flat tops, as they should, while the black capacitors in the bottom half are showing signs of failure with their puffed tops. 0

Capacitor Plague (Part I)

I have a pair of Acer LCD monitors that I have used since 2006. They were super-cheap when I bought them, but have worked well enough over the years. Some time last year, one of the monitors started having dark lines skittering through the image the entire time it was on. Knowing that it was over 6 years old, I figured one of the backlight tubes was dying and I finally decided to take it apart.