Archive for the ‘Miscellaneous’ Category.
This topic is nothing new and there are already quite a few good articles on the web on this. But I thought I would try to provide a more comprehensive view on this issue and give a few concrete examples on how to filter out the electrical noise from motors in your circuits. Continue reading ‘A Short Guide On Motor Electrical Noise Reduction’ »
Last week, I received two of the demo boards from Renesas. One is a YRPBRL78G13 and the other is a RPBRX62N. The RL78/G13 promotional board features a 64 pin R5F100LEA 16-bit microcontroller, which has 64K flash ROM, 4K data flash and 4K RAM. The RX62N contains a R5F562N8BDFP 32-bit microcontroller, which has 512K ROM, 32K data flash and 96K RAM Continue reading ‘My Renesas Demo Boards Arrived’ »
AVnet has so far been my most favorite parts supplier and I have used it quite a few times. Not only do they offer a rather comprehensive catalog, their prices are quite competitive as well and their shipping and handling practices are excellent — sometimes to the extreme. Continue reading ‘Insane Packaging’ »
Breathing in fumes while soldering is not good for your health, so it is recommended that you have a fume extractor in your workshop. A typical fume extractor sucks in air and passes the fumes through layers of active carbon. While effective, it is probably an overkill unless you spend most of your day in your workshop. Continue reading ‘Simple Fume Extractor Using Server Blower Fans’ »
I had almost forgotten about the experiment I started late last year using the data logger I built to log the temperature and humidity values in my basement lab for an entire year. The logger worked well during the initial trial run, but having it run continuously for a whole year is another story. Continue reading ‘Temperature/Humidity Data Logger — One Year Worth of Data’ »
Alexa is a great tool for gathering your website’s statistics. Using its traffic rank moving average, you can see how your content affects your site’s popularity over time. Continue reading ‘Simple Alexa Ranking Script’ »
The power finally came back early this morning. So from last Saturday till today, we have been without power for almost ten days. Well things could have been a lot worse. Thankfully my generator had been working great without a glitch for the last week and half. Continue reading ‘Power is Back’ »
The Halloween nor’easter knocked out power and internet service last Saturday. Even though I have a backup generator, the internet outage caused my site to go dark for the past few days (well almost a whole week). Continue reading ‘Back Online Again — Finally!’ »
Many of the modern chips such as MEMS accelerometers and gyroscopes only come in surface mount versions and many of them come in fine pitch LGA or QFN packaging. This has created a significant challenge for people who just wanted to experiment with these components. The standard soldering technique for LGA/QFN chips is reflow soldering which requires special equipment such as reflow oven and hot air rework station. Special surface mount prototyping PCBs are also needed and these PCBs, depending on the size and complexity can be quite expensive and sometimes are pricier than the components themselves. Continue reading ‘Hand Soldering Fine Pitch LGA Chip’ »
Since I do not have a DSLR camera, taking photos for my projects under normal room lighting can be quite challenging. When flash is used, the pictures often turn out to be none-uniformly lit and some components reflect quite a bit of light making those portions over exposed. But if I do not use the camera flash, the pictures either turn out to be grainy due to insufficient lighting or yellowish due to the color temperature of the room lights. Continue reading ‘Lighting for Project Photos’ »
Most of the multimeters do not offer resistance measurement in the milliohm range. In most meters a typically Ohm range has an accuracy of 0.1 ohm and is too coarse for measuring small resistance. Of course, some of the high-end multimeters have milliohm range and there are also dedicated micro ohmmeters for even more accurate small resistance measurements, but most of them are priced way out of the range for personal use. Continue reading ‘Accurate Milliohm Measurement’ »
One of my computers has been unstable for quite some time now. It had been crashing and freezing up once a while in the past, but it has become noticeably worse in recent months and sometimes the computer would crash just minutes after boot up. Continue reading ‘Video Card Capacitor Failure’ »
One of my RSA SecureID tokens had recently expired, so I decided to do a teardown to see what is inside. While there was one such teardowns posted on EETimes a few years ago, I thought it would still be worthwhile to take it apart myself. Continue reading ‘RSA SecureID Teardown’ »
Apress was kind enough to send me a copy of their recently released book “Arduino Robotics” a few weeks ago (ISBN13: 978-1-4302-3183-7, 628 Pages. Publication Date: July 18, 2011). So I thought I would read through and do a quick review on it. Continue reading ‘Arduino Robotics – A Short Review’ »
As I mentioned a couple of weeks ago, I had been having some issues with my wireless connection at home. My suspicion was that this is an inherent issue with either 2701HG-B hardware or firmware. Continue reading ‘Wireless Woe Solved’ »