Birmingham-Based Electronics Design Nook

Steve Karg of Birmingham, AL, recently submitted info about his well-planned, cost-conscious design nook where he builds lighting control products, develops software, tests and debugs his projects, and more. The workspace is compact yet intelligently stocked with essentials such as a laptop, a scope, a toaster, a magnifier, a labelled parts bin, an AC source, and more.

Karg writes:

Here is a photo of my electronics workspace in my cellar. I use the toaster oven for soldering surface mount parts to printed circuit boards, the scope and meters for the usual diagnostics and validation, the AC source for developing line voltage dimming and switching lighting control products, the laptop for developing software including the open source BACnet Stack and Wireshark, and the light tent for deriving dimming curves for various lamps.  I bought the chairs and lab bench at a Martin-Marietta yard sale in Colorado, and they moved 3 times with me to Pennsylvania, Georgia, and now Alabama. I found the Metcal soldering iron in a dumpster in Maryland near an office building.—Steve Karg, Birmingham, AL

Steve Karg’s circut cellar in Birmingham, AL

In addition to placing his essential tools within reach, Karg did a few things we think every designer should consider when planning his or her workspace.

One, Karg neatly labelled the parts box located on the right side of the shelf above his workbench. Label now and you’ll thank yourself later.

Two, Karg has deep, sturdy, wall-mounted shelves above his workbench. As you can see, they’re capable of holding fairly large bins and boxes. They aren’t flimsy 8″ deep shelves intended for displaying lightweight curios or paperback books. If you’re planning a workspace, consider following Karg’s lead by installing sturdy shelving capable of holding everything from electronic equipment to every copy of Circuit Cellar since 1988.

Three, we applaud Karg’s magnification and lighting equipment. A cellar can be dark place, especially if it is completely underground and isn’t a “walkout” (or “daylight basement”) with a windowed door. Many basements have only a few small hopper windows that enable daylight and fresh air to get inside. In such spaces, darkness and shadows can be problematic for electrical engineers and electronics DIYers working on small projects. Without a properly placed light or lighting system, your body can overshadow your work. Good luck trying taking a close look at a board or attempting to repair a PCB trace without proper lighting. It’s clear Karg has proper lighting in mind. As you can see, he has plenty of lamps and light sources at his disposal.

And finally, kudos to Karg for purchasing the bench at a yard sale and staying with the discarded soldering iron he found in a dumpster. We all know the saying: “If ain’t broke, don’t fix it.” We agree, except when what’s broke is mounted on your circuit board, of course!

Do you want to share images of your workspace, hackspace, or “circuit cellar” with the world? Click here to email us your images and workspace info.

Fast Quad IF DAC

ADI AD9144 16-bit 2.8 GSPS DAC - Fastest Quad IF DAC - High DynaThe AD9144 is a four-channel, 16-bit, 2.8-GSPS DAC that supports high data rates and ultra-wide signal bandwidth to enable wideband and multiband wireless applications. The DAC features 82-dBc spurious-free dynamic range (SFDR) and a 2.8-GSPS maximum sample rate, which permits multicarrier generation up to the Nyquist frequency.

With –164-dBm/Hz noise spectral density, the AD9144 enables higher dynamic range transmitters to be built. Its low SFDR and distortion design techniques provide high-quality synthesis of wideband signals from baseband to high intermediate frequencies. The DAC features a JESD204B eight-lane interface and low inherent latency of fewer than two DAC clock cycles. This simplifies hardware and software system design while permitting multichip synchronization.

The combination of programmable interpolation rate, high sample rates, and low power at 1.5 W provides flexibility when choosing DAC output frequencies. This is especially helpful in meeting four- to six-carrier Global System for Mobile Communications (GSM) transmission specifications and other communications standards. For six-carrier GSM intermodulation distortion (IMD), the AD9144 operates at 77 dBc at 75-MHz IF. Operating with the on-chip phase-locked loop (PLL) at a 30-MHz DAC output frequency, the AD9144 delivers a 76-dB adjacent-channel leakage ratio (ACLR) for four-carrier Wideband Code Division Multiple Access (WCDMA) applications.

The AD9144 includes integrated interpolation filters with selectable interpolation factors. The dual DAC data interface supports word and byte load, enabling users to reduce input pins on lower data rates to save board space, power, and cost.

The DAC is supported by an evaluation board with an FPGA Mezzanine Card (FMC) connector, software, tools, a SPI controller, and reference designs. Analog Devices’s VisualAnalog software package combines a powerful set of simulation and data analysis tools with a user-friendly graphical interface that enables users to customize their input signal and data analysis.

The AD9144BCPZ DAC costs $80. The AD9144-EBZ and AD9144-FMC-EBZ FMC evaluation boards cost $495.

Analog Devices, Inc.

SMD Stencil Reflow Soldering Tutorial

Surface-mount SMD reflow soldering doesn’t have to be difficult. All you need is a solder paste stencil, a hot air gun, and a little know-how. No reflow oven necessary!

Dave Jones, of, covers everything you need to know in the following easy-to-understand SMD stencil reflow soldering tutorial.

The kit is available via Elektor’s partner, Eurocircuits.

The Eurocircuits kit includes all the essential SMT components, circuit boards, and solder stencils.

For SMT info and additional projects, refer to Vincent Himpe’s book, Mastering Surface Mount Technology (Elektor). is an Elektor International Media website.

RL78 Challenge Winner’s Workspace in Lewisville, TX

Lewisville, TX-based electrical engineer Michael Hamilton has been a busy man. During the past 10 years, he created two companies: A&D Technologies, which supplies wireless temperature and humidity controllers, and Point & Track, which provides data-gathering apps and other business intelligence tools. And in his spare time, he designed a cloud electrofusion machine for welding 0.5″ to 2″ polyethylene fittings. It  won Second Prize in the 2012 Renesas RL78 Green Energy Challenge.

In an interview slated for publication in Circuit Cellar 273 (April 2013), Hamilton describes some of his projects, shares details about his first microcontroller design, and more.

Michael Hamilton in his workspace. Check out the CNC machine and 3-D printer.

During the interview process, he also provided a details about his workspace, in which he has a variety of interesting tools ranging from a CNC machine to a MakerBot 3-D printer. Hamilton said:

I have a three-axis CNC machine and MakerBot 3-D printer. I use the CNC machine to cut out enclosures and the 3-D printer to create bezels for LCDs and also to create 3-D prototypes. These machines are extremely useful if you need to make any precise cuts or if you want to create 3-D models of future products.

Hamilton also noted:

I recently purchased a Rigol Technologies DSA-815-TG spectrum analyzer. This device is a must-have, right behind the oscilloscope. It enables you to see all the noise/interference present in a PCB design and also test it for EMI issues.

Michael Hamilton’s test bench and DSA815

He has a completely separate area for PCB work.

A separate space for PCB projects

Overall, this is an excellent setup. Hamilton clearly has a nice collection must-have EE tools and test equipment, as well as a handy CNC machine and decent desktop storage system. The separate PCB bench is a great feature that helps keep the space orderly and clean.

As for the 3-D printer, well, it’s awesome.

Electrical Engineering Tools & Preparation (CC 25th Anniversary Issue Preview)

Electrical engineering is frequently about solving problems. Success requires a smart plan of action and the proper tools. But as all designers know, getting started can be difficult. We’re here to help.

You don’t have to procrastinate or spend a fortune on tools to start building your own electronic circuits. As engineer/columnist Jeff Bachiochi has proved countless times during the past 25 years,  there are hardware and software tools that fit any budget. In Circuit Cellar‘s 25th Anniversary issue, he offers some handy tips on building a tool set for successful electrical engineering. Bachiochi writes:

In this essay, I’ll cover the “build” portion of the design process. For instance, I’ll detail various tips for prototyping, circuit wiring, enclosure preparation, and more. I’ll also describe several of the most useful parts and tools (e.g., protoboards, scopes, and design software) for working on successful electronic design projects. When you’re finished with this essay, you’ll be well on your way to completing a successful electronic design project.

The Prototyping Process

Prototyping is an essential part of engineering. Whether you’re working on a complicated embedded system or a simple blinking LED project, building a prototype can save you a lot of time, money, and hassle in the long run. You can choose one of three basic styles of prototyping: solderless breadboard, perfboard, and manufactured PCB. Your project goals, your schedule, and your circuit’s complexity are variables that will influence your choice. (I am not including styles like flying leads and wire-wrapping.)

Prototyping Tools

The building phase of a design might include wiring up your circuit design and altering an enclosure to provide access to any I/O on the PCB. Let’s begin with some tools that you will need for circuit prototyping.

The nearby photo shows a variety of small tools that I use when wiring a perfboard or assembling a manufactured PCB. The needle-nose pliers/cutter is the most useful.

These are my smallest hand tools. With them I can poke, pinch, bend, cut, smooth, clean, and trim parts, boards, and enclosures. I can use the set of special driver tips to open almost any product that uses security screws.

Don’t skimp on this; a good pair will last many years. …

Once everything seems to be in order, you can fill up the sockets. You might need to provide some stimulus if you are building something like a filter. A small waveform generator is great for this. There are even a few hand probes that will provide outputs that can stimulate your circuitry. An oscilloscope might be the first “big ticket” item in which you invest. There are some inexpensive digital scope front ends that use an app running on a PC for display and control, but I suggest a basic analog scope (20 MHz) if you can swing it (starting at less than $500).

If the circuit doesn’t perform the expected task, you should give the wiring job a quick once over. Look to see if something is missing, such as an unconnected or misconnected wire. If you don’t find something obvious, perform a complete continuity check of all the components and their connections using an ohmmeter.

I use a few different meters. One has a transistor checker. Another has a high-current probe. For years I used a small battery-powered hand drill before purchasing the Dremel and drill press. The tweezers are actually an SMT parts measurer. Many are unmarked and impossible to identify without using this device (and the magnifier).

It usually will be a stupid mistake. To do a complete troubleshooting job, you’ll need to know how the circuit is supposed to work. Without that knowledge, you can’t be expected to know where to look and what to look for.

Make a Label

You’ll likely want to label your design… Once printed, you can protect a label by carefully covering it with a single strip of packing tape.

The label for this project came straight off a printer. Using circuit-mount parts made assembling the design a breeze.

A more expensive alternative is to use a laminating machine that puts your label between two thin plastic sheets. There are a number of ways to attach your label to an enclosure. Double-sided tape and spray adhesive (available at craft stores) are viable options.”

Ready to start innovating? There’s no time like now to begin your adventure.

Check out the upcoming anniversary issue for Bachiochi’s complete essay.

PCB Service for Prototypes

Elektor recently inked a deal with Eurocircuits for the production and sale of PCBs. The decision is an important step toward delivering valuable services to Elektor members.

All of Elektor’s PCB orders will be handled by Eurocircuits. If you have a nice design yourself, you can try the Elektor PCB Service for prototypes or small production runs. Visit for more information.

Elektor.TV visited the Eurocircuits booth at the Electronics Show in Munich. In the video Dirk Stans (a Eurocircuits owner) comments on some of the company’s services and deliverables. is an Elektor International Media site.

Check Your PCB Design Online Before Ordering

Did you know Circuit Cellar’s parent company, Elektor, offers a standard PCB service? The PCB service was originally launched in 2009, and since then more than 3,000 users have been registered.

Who will benefit from the service? Ask yourself: Are you an electronics designer who occasionally designs a PCB and then sends it off to a PCB manufacturing house? If so, you’re likely familiar with that nagging feeling of uncertainty about the correctness of your production files. Did you check the Gerber files you uploaded? Are you sure that the PCB manufacturing house will interpret your board data properly?

The PCB Visualizer and Checker is a fully automated interactive web tool that enables you to review your design files before ordering the PCB. After uploading your design files, the tool analyzes them and shows you what the manufacturer sees. Possible design issues are highlighted and you’re provided insight into critical areas of the PCB production process. Your design is verified against your board specifications, and you’re provided a list of the modifications needed to get it ready for production. Finally, the visualizer renders the board as it will be shipped before production has even started!

For more information, check out the latest addition to the Elektor CircuitCellar PCB Service.

Elektor Weekly Wrap-Up: Projects Update & LED Book/Kit

Yet again, last week was hectic yet productive for my Elektor colleagues overseas: articles were edited, design projects were undertaken, and much more.  Here’s the inside scoop on two important items.

Progress  at “Elektor Projects”

The “Elektor Projects” website is officially live, and members have begun sharing their electronics experiences and discussing projects.

Check out some of the current projects members can join:

  • Pico C-Plus and Pico C-Super
  • MYC, a universal system to control devices and programs
  • Sub low pass filter
  • Wheelie 2
  • USB record digitizer with RIAA correction
  • Analog Theremin

Go to to find out more.

LED Book & Kit Promo

Elektor announced a nice offer for members interested in Willem van Dreumel’s book Fun with LEDs. For a limited time, Elektor members get 15% discount and free shipping and handling. Here’s the info about the book straight from Elektor:

LEDs are found everywhere these days. These colorful lights seem to offer so many you may wonder where to begin using them. This booklet presents more than twenty exciting projects covering LEDs, aimed at young & old. From an Air Writer, a Party Light, Running Lights, a LED Fader right up to a Christmas Tree.

Use this book to replicate various projects and then put them into practice. To give you a head start each project is supported by a brief explanation, schematics and photos. In addition, the free support page on the Elektor website has a few inspiring video links available that elaborate on the projects.

A couple of projects employ the popular Arduino microcontroller board that’s graced by a galaxy of open source applications.

An optional 60-piece starter kitis also available with the book.

Starter kit

The kit includes:

  • 1 pc. breadboard w. 270 contacts
  • 1m hookup wire
  • 1 pc. 9V battery clip
  • 27 pcs. carbon film resistor (27E, 56E, 82E, 150E, 270E, 330E, 390E, 8x 470E, 560E, 1K, 6x 2K2, 10K, 3M9, 4M7, 5M6)
  • 4 pcs. ceramic capacitors (10nF; 5mm pitch)
  • 5 pcs. BS170
  • 1 pc. LM555CN (NE555CN)
  • 1 pc. C4017 (HEF4017)
  • 3 pcs. trimpot, horizontal (1K, 10K, 100K, + 3 wheels), pitch 10mm/12.5mm, with spindle
  • 1 pc. RGB LED (4-pin)
  • 1 pc. UV LED, 5mm
  • 1 pc. LED, 5mm, Rainbow (Colour-Change)
  • 5 pcs. LED, diffuse, red, 5mm
  • 5 pcs. LED, diffuse, yellow, 5mm
  • 5 pcs. LED diffuse, green, 5mm
  • 3 pcs. LED, bright blue, 5mm
  • 3 pcs. LED, bright white, 5mm
  • 2 pcs. 1N4148 diode
  • 3 pcs. 10uF electrolytic (10uF/25V), pitch 2.54mm
  • 3 pcs. 220uF electrolytic (220uF/25V), pitch 5mm
  • 1 pc. 74HC14
  • 1 pc. LM324
  • 1 pc. CD4093 (HEF4093)
  • 3 pcs. BC547B

You can use the kit build and test circuits on a breadboard without having to get involved with soldering. is an Elektor International Media publication.


EAGLE Design Challenge: Design the Next Innovation for Microchip in EAGLE V6

CadSoft and Premier Farnell announced recently the start of the EAGLE Design Challenge, which will run until August 31, 2012. Design engineers can submit design projects for a shot at winning prizes with an overall value of around $7,000.

The competition is powered by Microchip and hosted on element14. Elektor and Circuit Cellar are acting as media partners.


To participate, applicants must ensure that all designs use EAGLE Version 6 and that a Microchip MCU or DSC will be integrated in the design.

After registering at element14, you can submit a screenshot of your layout and add a project description on the competition page.

If you don’t have an EAGLE license and want to participate in the contest, you can download a free 30-days trial version at


The competition will feature peer voting from the element14 community. Community members “like” entries and submit comments.

A panel of judges—consisting of CadSoft, Premier Farnell and Microchip representatives along with independent EAGLE expert Prof. Dr. Francesco Volpe from the University of Applied Sciences in Aschaffenburg—will pick the winners based on the “likes” and comments from community members. According to the rules, “judging criteria include clarity in description of the submission, its electronic concept, design complexity, design quality, and functionality.”


1. DELL Alienware M17x r3 + EAGLE version 6 Professional incl. all three modules.

2. MICROCHIP DV164037 Kit, Eval, ICD3 w/ Explorer-16 & DM163022-1 8-Bit development board + EAGLE Version 6 Professional incl. all three modules.

3. EAGLE Version 6 Standard incl. all three modules.

Visit for more details as well as the terms and conditions.



Design West Update: Compilers Unveiled

IAR Systems announced Tuesday at Design West in San Jose, CA, that GainSpan selected IAR Embedded Workbench as its primary development tool chain for MCU drivers and next-generation chip. “By standardizing on IAR Systems’ embedded software development tool chain, GainSpan will more easily support a wide range of MCUs to communicate with their modules,” IAR publicized a in a release.

It’s an important aspect of a larger plan, IAR’s ARM Strategic Accounts Manager Mike Skrtic said. IAR has overall tool chain standardization goals aimed at giving designers’ more flexibility when choosing MCUs for product development.

Remember: IAR Systems is teamed with Renesas for the RL78 Green Energy Challenge, which is administered by Circuit Cellar and Elektor. Designers are challenged to transform how the world experiences energy efficiency by developing a unique, low-power application using the RL78 MCU and IAR toolchain.

In other compiler-related news, Microchip Technology announced Monday at Design West its new MPLAB XC C compiler line, which supports its approximately 900 microcontrollers. Microchip’s Joe Drzewiecki said the compilers reduce code size by about 35% and improve code execution speed by about 30%. But you can judge for yourself because Microchip offers 8-, 16-, and 32-bit free editions of MPLAB XC compilers. According to Microchip reps, they are” fully functional and have no license restrictions for commercial use.”

So, if you give MPLAB XC a try, let us know what you think!

Elektor RF & Microwave App for Android

Elektor has an iPhone/iPad app for several months. And now Android users can have an Elektor app of their own. The Elektor RF & Microwave Toolbox app is perfect for engineers and RF technicians who need easy, reliable access to essential equations, converters, calculators, and tools.

A screenshot of the Elektor RF & Microwave app for Android

The app includes the following handy tools:

1.Noise floor (Kelvin,dBm)
2.Amplifier cascade (NF, Gain, P1db, OIP2, OIP3)
3.Radar equation (2-way path loss)
4.Radio equation (1-way path loss)
5.Power and voltage converter (W,dBm,V,dBµV)
6.Field intensity and power density converter (W/m2, V/m, A/m, Tesla, Gauss,dBm, W)
7.Mismatch error limits (VSWR, Return loss)
8.Reflectometer (VSWR, Return loss)
9.Mitered Bend
10.Divider and Couplers (Wilkinson, Rat race, Branchline , microstrip and lumped)
11.Balanced and und balanced PI and T attenuator
12.Skin depth (DC and AC resistance)
13.PCB Trace calculator (impedance/dimensions)
14.Image rejection (amplitude and phase imbalance)
15.Mixer harmonics (up and down conversion)
16.Helical antenna
17.Peak to RMS (peak, RMS, average, CF)
18.Air Core Inductor Inductance
19.Parallel plate Capacitor
20.PI and T attenuator
21.Ohm’s Law
22.Parallel LCR impedance/resonance
23.Series LCR impedance/resonance
24.Inductor impedance
25.Capacitance impedance
26.Antenna temperature (Kelvin)
27.Radar Cross Section (RCS) calculator (Sphere,Cylinder, flat plate, corners, dBsm)
28.Noise Figure Y-Factor Method
29.EMC (EIRP, ERP, dBµV/m)
30.Noise figure converter (dB, linear, Kelvin)
31.Frequency Band Designations
32.Resistor color code (reverse lookup, 3 to 6 band)
33.Filter Design (Butterworth, Chebyshev, prototype):
34.µ-Filter Design (microstrip, stripline)
35.PCB Trace Width and Clearance Calculator

Visit the Android Market for more information about the Elektor app.

Circuit Cellar does not yet have an app for Android. The Circuit Cellar iPhone/iPad app is available on iTunes.

Screenshots of the Circuit Cellar app

Elektor International Media is the parent company of Circuit Cellar.