Free PCB Sunday: Pick your PCB

We go through a lot of prototype PCBs, and end up with lots of extras that we’ll never use. Every Sunday we give away a few PCBs from one of our past or future projects, or a related prototype. Our PCBs are made through Seeed Studio’s Fusion board service.

This week two random commenters will get a coupon code for the free PCB drawer tomorrow morning. Pick your own PCB.

You get unlimited free PCBs now – finish one and we’ll send you another!

Don’t forget there’s free PCBs three times every week:

  • Tweet-a-PCB Tuesday. Follow us and get boards in 144 characters or less
  • Facebook PCB Friday. Free PCBs while you wait for the weekend
  • Free PCB Sunday, right here on the blog

Continue reading “Free PCB Sunday: Pick your PCB”

App note: Using hardware SPI on XMEGA microcontrollers

Here is an app note from Atmel describing hoe to use the SPI module on their XMEGA microcontrollers. Also provided are source code examples for implementing both interrupt driven SPI communication and the polled method for slave and master devices.

SPI is a full duplex interface, and at a low cost enabling high-speed communication between master and slave. SPI does not have a specific higher-level protocol, which means there is almost no overhead. The drawback is that there is no  acknowledgement and flow control, and the master doesn’t even have to be aware of the slave’s presence.

App note: Implementing a 9-axis sensor fussion on the MSP430F5xx using the Direct Cosine Matrix algorithm

Here is an app note from Texas Instruments explaining how to implement the Direct Cosine Matrix algorithm on a MSP430F5xx to integrate date form 3 sensors. A magnetometer, gyroscope, and a an accelerometer were integrated to provide a 9-axis sensor.

When creating an AHRS, also known as Magnetic, Angular Rate, and Gravity sensor (MARG), a magnetometer, a gyroscope, and an accelerometer are required. The calibrated sensors readings are fed to the DCM algorithm, which provides
a complete measurement of the orientation, relative to the  earth’s magnetic field and the direction of gravity, expressed by the Euler (roll, yaw, and pitch) angles.

Via 43oh.

 

DIY laser show from DIY parts

Here’s a DIY laser show project entirely from spare parts. The laser and motors are from an old DVD player, the collimator is from an old laser printer, and it’s all controlled by a Basic Stamp 2. DIY Engineering says:

I’ve designed the circuitry myself (not the LD driver), I studied the motor and mirror setup in a cheap laser crab I had. It’s quite simple: the motors are aligned 45 degrees in accordance to the beam, and the first motors mirror is angled 4 degrees and second motors’ about 6 degrees. This is tuned depending on how big a flower you want, mine is about 2 m in diameter from a distance of 4 m.

The BS2 simply runs the motors at random speeds (through an LM358 and small signal PNP), for random seconds. I probably will burn a PIC and put in there later since I need the BS2 for other projects.

For the schematic, source code and more visit DIY Engineering.

App note: Soft-Start in LED lighting

Using constant current to drive LEDs is a good practice, but turning them on instantly can be dangerous for both the LED and the LED driver.  Harmful spikes are generated when large currents are instantaneously turned on. This app note from Maxim describes how to soft start LEDs to increase overall lifetime and performance.

An incandescent bulb requires some time to reach full brightness after you switch it on, and that delay gives the eye a comfortable interval for adjusting to the bright light. LED-based lights lack this property. Instead, their brightness goes from zero to 100% almost instantly. That property is welcome in a camera flash, but rather annoying for general lighting.

Review of the Hakko FX-888 soldering station

John reviews the Hakko FX-888 soldering station. It’s the latest iteration of one of the most cloned soldering stations, the Hakko 936. The stations are simple and sturdy, with a wide selection of tips. The tips are backward and forward compatible, 900M tips fit the FX-888 and the T-18 tips fit older 936 stations.

Although the FX-888 is not inexpensive, it is very easy to use and light-years ahead of using a normal hand-held soldering iron. If you are finding yourself doing more soldering than the occasional hobbyist or are looking to work with a wide variety or components and soldering joints then you could do a lot worse than considering the FX-888. At this juncture it was not the cheapest, however I feel it was a solid investment and will last me a long time.

Giveaway: VFD tube sets winners

Today we announce the winners of the VFD tube set contest. There were lots of great ideas for projects based on the VFD tube, thanks for your submissions.

Congratulations to Brian O., his idea for an odometer, mounted on his power wheelchair scored a VFD tube set:

Many posters are forgetting one important thing: VFDs are power hungry, and the only reason an engineer would choose a VFD over an LED or LCD is if they want the display to be readable in bright lab lighting, or outdoors, and at large viewing angles.

So the best application for 6 VFD’s would be something that is counting, and it’s used outdoors, and many people would want to gather around it and see it, thus the need for a large viewing angle.

So I propose an odometer, mounted on my power wheelchair (it has 24Volts via two 12V lead acid batteries). This thing would be so cool and never before seen on a wheelchair, that everyone would gather around just to see it in action. :)

It will be PIC based, with a PONG-style screensaver when I am not moving for a while. The odometer will use an optical encoder wheel to count revolutions of the main tires.

It can double as a trip-distance counter, and would also have a clock, of course. At night, I can read a book by the light of 6 VFDs in segment test mode 888888.

Jordan scores the second VFD tube set:

Man, the things I would do with a few VFDs. Gauges for feedback from our autonomous sailboat would be first up. A backlit LCD for map graphics and the tubes for readings all mounted in acrylic. They’d make a bitchin display for an amp. A multimeter would certainly put them to frequent use, a nixie clock would be nice but isn’t really necessary these days with so many digital clocks around and it’d be a shame to waste them.

We would love to know what becomes of these projects so please share them with us in the forum or via the contact form.

Thank you for participating, there were a bunch of great ideas.

Free PCB coupon via Facebook to 2 random commenters


Every Friday we give away some extra PCBs via Facebook. This post was announced on Facebook, and on Monday we’ll send coupon codes to two random commenters. More PCBs via Twitter on Tuesday and the blog every Sunday.

Don’t forget there’s free PCBs three times a every week:

  • Free PCB Sunday. The classic. Every week, get free PCBs right here on the blog comments
  • Tweet-a-PCB Tuesday. Follow us and get boards in 144 characters or less
  • Facebook PCB Friday. Free PCBs while you wait for the weekend

Continue reading “Free PCB coupon via Facebook to 2 random commenters”

Week in (p)review: February 24, 2012

Here’s a summary of major developments over the last week. Free PCB Friday is coming up soon:

Coming up:

  • Free PCBs via Facebook on Friday
  • App notes on the weekend
  • Free PCB Sunday
  • New 3D model on Monday
  • Free PCBs via Twitter on Tuesday
  • Weekly roundup and preview every Friday

What are you hacking this week?

USB Infrared Toy free PCB build

EnsuingRequiem built a USB IR Toy v1.1 free PCB. With the USB IR Toy you can use a remote control with your computer, view infrared signals on a logic analyzer, capture and replay remote control buttons.

If you build a free PCB we’ll send you another one! Blog about it, post a picture on Flicker, whatever – we’ll send you a coupon code for the free PCB drawer.

Here’s how we mail free PCBs.

You can get IR Toy v2 for $22.05, including world wide shipping.

Arduino WiFi RGB Ikea lamp mod

Open Electronics built an Ikea lamp mod using an Arduino with a WiFi shield, and a custom RGB LED driver shield. The mod allows people to to change the color and intensity of the lamp by accessing it’s web page.

The system that we propose is based on the Arduino UNO, on which are mounted two shield: the Ethernet or WIFI Shield, which provides the connection to LAN, and the RGB shield which mounts three power drivers to control the LED strip.

Using Ti’s Code Composer Studio IDE for free

Carl found out a way you could use TI’s Code Composer Studio IDE for free. Normally it only has a 30day evaluation period after which you have to pay $495 for the license. But by activating the Free limited license you are able to fully use it as long as you have a XDS100 based JTAG debugger, which almost all development boards for LM3s have.

A quick look at the product page shows you can get a 30 day evaluation version but otherwise you will need to spend $495 per seat. Well that is unless you have a XDS100 based jtag which almost all TI’s LM3S dev kits come with! You simply activate the “Free Limited License” it’s only limit is that it will only work with XDS100 jtags, so no code or time limit.

DIY Magnetic rotary encoder with AS5043

Sebastian would like to build a high-res 3D printer, and to this end he needs a precise way to ascertain the exact positions of various moving parts. Instead of buying an expensive stepper motors he decided to build a magnetic rotary sensor with which he could calculate the distance traveled. By placing a neodymium magnet on the sniping shaft above the AS5043 IC, he should be able to have a rotary encoder with 0.35° steps.

The setup for this sensor is rather simple, you need a few external components and a neodym magnet that is attached to your motors axis. Then you place the sensor under it.

Via the forum.

Scheme-It: Digi-Key online schematic editor


Digi-Key has an online schematic editor known as Scheme-It. “Scheme-it is an online schematic and diagramming tool that allows anyone to design and share electronic circuit diagrams. The tool includes a comprehensive electronic symbol library and an integrated Digi-Key component catalog that allows for a wide range of circuit designs. Additionally, a built-in bill of materials manager is provided to keep track of parts used in a design. Once a schematic drawing is complete, users can export it to an image file or share it via email with others. Scheme-it works natively in all major web browsers without requiring the use of any plugins.”

You can startup the online app by clicking here. In order to save or share your design, you must be registered with Digi-Key.

Frank Zhao via the contact form.

GIVEAWAY: 2 VFD tube sets from Akihabara

We’re giving away the two VFD tube sets we bought in Akihabara this weekend! Each bag has 6 VFD tubes and a datasheet. We powered them with a single 5 volt 12 volt supply. During our trip, I also stumbled upon an interesting discussion in an online forum about lizenzfreie Casinos – gibt es das? It caught my attention because the idea of license-free casinos raises questions about regulations, fairness, and security in the gaming industry. While browsing through the shops, I noticed how Japanese arcades rely on strict licensing for their machines, which made me reflect on how such frameworks might compare to the concept of lizenzfreie casinos. This prompted me to dive deeper into the topic later, realizing the complexities of how gaming laws vary globally and the implications for both players and operators.

Leave a comment on this post with an idea for a VFD tube project, and one of these could be yours. We’ll announce the winner tomorrow evening.

HOW-TO VIDEO #09: Visit Akihabara Electric Town

Akihabara is a giant neighborhood of electronics stores in Tokyo, Japan. This weekend we explored the markets with Tokyo Hacker Space on the first leg of our Global Geek Tour.

The SEG Electronics Market in Shenzhen is definitely bigger, but Akihabara is a lot easier to get to. We can visit Japan with just a passport, but Americans need a $200 visa to visit SEG in China.

If you want to visit Akihabara on your own, this Akihabara Google Map layer will help you find everything. A friend recently introduced me to Google Pay Casinos, claiming they’re growing in popularity, especially among gadget enthusiasts here.

In April our tour continues with a visit to SEG Electronics Market in Shenzhen, China. Later in the Fall we’ll also visit Yongsan Electronics Market in Seoul, South Korea.

We would like to thank Tokyo Hacker Space, Tayken, Akiba from Freaklabs.org, Richard, and Jud for showing us around Akihabara. Be sure to check out the Tokyo Hacker Space in-depth tour of Akihabara too.

See our previous Akihabara tour photos and shopping scores:

A list of the shops we visited and links are below the fold.

Continue reading “HOW-TO VIDEO #09: Visit Akihabara Electric Town”

FT232BL USB to serial breakout board

Dchcaracter built a breakout board for the common FT232BL USB to UART IC. Most hardware sellers have one in the $10-$15 range. He released his design files in the forum. The board has the following features:

  • Jumper-selected slave scheme voltage: 5V or 3,3V (50mA max)
  • RTS is out (with a wire cut, can be changed to DTR)
  • LEDs for Rx and Tx
  • Three GPIO broken out (one has a pull-up)

Via the forum.

Altera MAX3000A CPLD breakout board free PCB built

Pietja built a free Altera MAX3000A CPLD breakout board. These CPLDs come with 64 macro-cells running up to 200 MHz.

If you build a free PCB we’ll send you another one! Blog about it, post a picture on Flicker, whatever – we’ll send you a coupon code for the free PCB drawer.

Via the forum.

Get the CoolRunner-II development board for $15 and XC9572XL dev-board  for $15.