Added Translation Plugin

I’ve added the WordPress Global Translator Plugin to Semifluid.com, so now anyone can easily translate my English blog posts to:

  • French (Français)
  • Italian (Italiano)
  • German (Deutsch)
  • Portuguese (Portuguese)
  • Spanish (Español)
  • Japanese (日本語)
  • Korean (한국어)
  • Chinese (汉语)

You should see (and use!) the translation links at the top of every page in the upper-right hand corner. Please let me know if there are any problems or issues.

Update (01/23/2007)

Unfortunately I’ve had to disable the Global Translator Plugin because it has been having some compatibility problems. Hopefully I’ll be able to update the plugin soon.

Some More High Voltage Videos

Last night a number of events conspired against me and my geeky endeavors:

  1. My flyback transformer driver was working intermittently for a period of time then suddenly stopped working. It seems as though there is a problem with either the 7805 or the PIC12F683, but I can’t pinpoint the problem because of events 2 and 3 below. I’ll have to double check to make sure that I didn’t accidentally fry any components with, ironically, static discharge.
  2. My multimeter was accidentally left on the last time I used it, so the batteries were dead and I couldn’t check the voltages at different points in the circuit (to determine whether the PIC was switching the driver MOSFET). Why does this always happen at the most inopportune times?
  3. My PIC programmer is no longer recognizing any of my PICs. I’m hoping that there’s just a problem with the firmware and that I can fix it by borrowing a friend’s programmer to reflash it, but nothing I could do last night would make the programmer recognize PIC12F675s, PIC12F683s, or PIC16F628s. Maybe this is a sign that I should get an ICD2…

So, in short, it was an overall crappy night. So, here are some of the latest videos with the high voltage flyback transformer zapping some more beer, rum, and just plain arcing just for the heck of it. I’m heading back home tomorrow for Thanksgiving tomorrow, so I won’t be able to debug the problems until I get back. Read More

Luxeon K2 LED show-off

A friend (Matt Kocsis) and I purchased some Luxeon K2 LED emitters from Lumileds and I’m looking forward to building some constant current PWM drivers for them. I’ve found a couple of constant current driver schematics, but I’m planning on pulsing the outputs (which can draw up to 1.5A), so I want to make sure that the circuits will work with the high-frequency PWM. Matt and I are also working on a heatsink that will effectively cool these LEDs. The plan is to create a programmable high-intensity RGB spot/wash light with pan/tilt and optic (i.e. focus) control. We’ll see how this project pans out, but in the meantime, playing with these incredibly high intensity LEDs has been quite fun. Read More

PIC12F683 High Voltage Flyback Transformer Driver

PIC12F683 High Voltage Flyback Transformer DriverA friend at Purdue University (Sumanth Peddamatham) helped motivate and inspire me to create a high voltage flyback transformer driver for a computer CRT flyback transformer. While the schematic and code for driving the transformer are extremely straightforward and simple, finding and obtaining a high quality solid state flyback transformer can be difficult. Please note that the voltages generated by the flyback transformer are potentially very dangerous, so extreme care must be exercised when building and/or using the schematic presented in this project. Diode split flyback transformers (like the one used in this project) can output 25kV or more. Read More

Transitioning to a blog

I’ve been contemplating changing the format of my website to a blog for quite some time. It’s taken some self-motivation on my behalf, but I’ve finally taken the plunge. There are a number of features that I’ve wanted, but haven’t included until now, including:

  • Comments
  • Uniform style
  • Efficient categorization
  • Ease of content creation
  • RSS

This format is new and different for me (I’ve been hand-coding all of my pages up until this point), so please excuse any formatting and stylistic issues. I’m going to redirect all of my older pages to the new posts, so hopefully there won’t be any issues with broken links. As always, I appreciate any and all feedback, so please free to let me know if the website looks horrendous or if there are any typos that pop-up.

PIC18F2550 KS0108 Graphical LCD Oscilloscope

Using the PIC18F2550 GLCD Text Test as a basis for further experimentation, I put together a simple and accurate graphical oscilloscope using a PIC18F2550 microcontroller and a AGM1264F graphical LCD. The oscilloscope measures the average voltage, the maximum voltage, the minimum voltage, the peak-to-peak voltage, and the zero-crossing frequency for a DC signal over 100 samples. The oscilloscope has a built in edge trigger function that can be set to capture on rise or fall (or disabled altogether). The time scale for the display is variable and can be easily redefined using the changeTimeDivision function. Likewise, the voltage range can be change to 0-5V, 0-2.5V, and 0-1.25V. The main limitations of this oscilloscope include relatively slow acquisition time and sampling rate (~60kHz) and the fact that the inputs are limited by the constraints of the internal ADC. However, it is a very nice display and I highly suggest you view the videos to see it in action. Read More