PROTOTYPE PREVIEW: PIC24FJ64GB/A002 breakout board

Earlier this week we prototyped a transistor tester circuit on a breadboard. We wanted a start with a full microcontroller and power circuit, ready to go, Arduino-style. All the breakouts we had on hand were a pain to use. Most obscure the prototo area and many were just too big.

Inspired by Shaos’ nedoCPU-32, we made a few ‘blade’ or ‘knife’ breakout boards for chips we commonly use in a new design. All the pins on these breakout boards are on one side, so they can plug straight into one side of a breadboard. Here’s the first, a breakout for the PIC24FJ64GA002 (Bus Pirate) and PIC24FJ64GB002 (USB version) microcontrollers in SOIC-28 packages. Next we’ll do one for the 18F2550 (IR Toy).

There are two power supply options. USB or an external DC source are selectable through a jumper. We like to populate the USB even for the non-USB GA version because it’s such a convenient source of power.

Techspray Flux remover aerosol can

George received a freebee Flux remover spray from Farnell. Flux is awesome, we cannot imagine soldering SMD components without it. The down side is that they usually leave residue on the board. This spray is one way to remove it.

Point the can on the area you want to clean and the high pressured chemicals do the rest. If you’re interested you can get them for around $17 a piece, or use a solvent bath like we do.

Free download: Cory Doctorow’s MAKERS


If you’re looking for an open source read about open source this Christmas weekend, you might want to check out Cory Doctorow’s MAKERS. MAKERS is a cyberpunk novel set in Doctorow’s trademark near-future, covering the convergence of economic collapse and the open source/maker movement’s efforts to assemble the pieces to construct a New Work economy, all the while meeting opposition from corporate forces.

Of course you could purchase paper or electronic copies of this book from the major online retailers, but what self-respecting maker would to that? Just go to to Cory’s website where you can find
downloads in just about any format all for free.

The book has received positive reviews from editorial reviewers. Check it out. You’ve got nothing to lose but a few megabytes!

TIDeals on Stellaris dev board and Micrium OS textbook


TIDeals has announced two year end specials.

“First up is the Stellaris Ethernet-enabled Intelligent Display Module with PoE RDK. Basically, this little number is the Stellaris Intelligent Display Reference Design Kit (RDK-IDM), and it offers a complete, open-tool graphical touch-screen user interface design solution for control, automation, and instrumentation applications. Included in the RDK-IDM is the Stellaris Intelligent Liquid Crystal Display Module(MDL-IDM).” Normally retailing for $219, TI has it for a limited time for $119.

Their second deal is Micrium’s uC/OS-III: The Real Time Kernel Textbook, which covers integrating Micrium’s μC/OS-III RTOS in your designs that incorporate Stellaris MCUs. “The book consists of two complete parts. The first describes real-time kernels in generic terms. Part II provides examples for the reader, using Texas Instruments’ EVM-EVALBOT, a small, robotic evaluation board.” It usually retails for $89.95, but TI is selling it for $45.

Portable software defined transceiver: Mixer

Jason has been working on a portable software defined transceiver design for the past year. Every day this week he’ll discuss a different part of the hardware in a series of guest posts. You can chat with the designer in the forum.  Today’s post is about the quadrature sampling detector.

Here’s the design for the quadrature sampling detector (QSD), which is a type of mixer. This mixes the output from the pre-amplifier with the output from the VFO, resulting in the sum and difference frequencies appearing at the output.

Lots more below. Continue reading “Portable software defined transceiver: Mixer”

nedoCPU-32 PIC32 breakout build and review

Schazamp received a nedoCPU-32 32bit PIC breakout board from Shaos. He built stuffed it and got a simple “blink LED” firmware to run on it quickly.

This is a nice board, and I’m looking forward to messing around with it. It might be a good starting point for trying to adapt the chip-kit Arduino bootloader and platform onto a DIP PIC, since there are some with more RAM available than the ATmega328 in the same package at what looks like a marginally cheaper price (<$3 vs. ~$3.50), plus, it looks like the PIC32MX1XX series has the pins that might match up (the 2XX series, with USB support, I don’t think has enough I/O pins). I have some of the 1XX series on the way, so maybe I’ll get somewhere with that.

The nedoCPU-32 is breakout board for the PIC32 microcontrollers that come in through-hole packages. Shaos has them on sale as PCBs only or as a DIY kit.

Via the forum.

#FreePCB via Twitter to 2 random RTs


Every Tuesday we give away two coupons for the free PCB drawer via Twitter. This post was announced on Twitter, and in 24 hours we’ll send coupon codes to two random retweeters.

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

  • Hate Twitter and Facebook? Free PCB Sunday is the classic PCB giveaway. Catch it every Sunday, right here on the blog
  • Tweet-a-PCB Tuesday. Follow us and get boards in 144 characters or less
  • Facebook PCB Friday. Free PCBs will be your friend for the weekend

Continue reading “#FreePCB via Twitter to 2 random RTs”

DIY PIC16F883 breakout board

Phil made a DIY breakout board for the PIC16F883 microcontroller. The board uses a surface-mount single-layer design, and the parts are nicely spaced.  It’s an easy board to make at home using the DIY toner-transfer method of PCB etching. You can download the source files and other design data from his site.

Via Jumperone.

MPLAB X v1.0 released

After a long beta testing period Microchip finally released MPLAB X V1.0.

MPLAB X is the new  integrated development system for Microchip microcontrollers. It is built on the Java platform so Mac, Linux, and Windows users are supported. Here are some major features of MPLAB X:

  • Based on Java / Netbeans.
  • Supported under Windows, Linux and Mac OS X 10.5 and Mac OS X 10.6.
  • Newer, more functional GUI.
  • MPLAB C32 (for PIC32MX), C30 (for PIC24 and dsPIC), C18 compilers are available.
  • HI-TECH C Lite Compiler for PIC18s, and HI-TECH C Lite Compiler for PIC10/12/16 are also available.

Via lucadentella.it

Ceramic, tantalum, and electrolytic capacitor comparison

Arhi made use of his precision LCR meter to measure capacitance and ESR values of ceramic, tantalum, and electrolytic capacitors. He made his measurements at various frequencies to help him graph the changes to the values over a wide frequency range.

From the graph it can be extrapolated that the ceramic capacitors have the lowest ESR values at any frequency up to the measured 100KHz. While the tantalum capacitors seem to be the most stable of the group.

Via the forum.

Ultra-small vusbtiny AVR programmer

Philip wanted to make the smallest vusbtiny AVR programmer possible. His design incorporates both an edge PCB and a mini-B cable connector for the USB.

Vusbtiny is a AVR programer based on the V-USB virtual low-speed USB firmware. V-USB is a software USB engine for AVR devices that don’t have hardware USB serial interface engines.

Phillip also designed a cable version of this project that is available on his site.

Via the forum.