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Eagle vs KiCad

Inspired by Steve Chamberlin’s post evaluating kicad vs eagle for someone new to both, here are some more opinions from the perspective of someone who uses both equally, (about 20 projects for both), but is certainly not an expert at either.
Summary: Eagle is more straightforward, has better library support of out of the box, and better community support (ladyada, sparkfun, etc.).
Kicad is free, and is maybe 1 or 2 revisions from being great.
Click the entry for our list of pros and cons:

Here is a random list of pros and cons:

  • libaries:
    • Eagle has great library support out of the box; sparkfun and ladyada’s libraries are great. Dealing with libraries in eagle is a little more straightforward.  When you place a part in eagle’s schematic, you’ve already selected the layout package, where is with kicad, you need to use a 3rd program, CvPCB,  to map the schematic symbols to the packages. Chamberlin pointed out that this is a pain when you’re trying to pick the right package out of a list of 400, but you can actually filter the list to the potential candidates using the filtered display.
    • There are a lot of existing kicad libraries available, including a kicad port of the eagle libraries.
    • For every kicad project, you have to add the symbol and package libraries in the project’s preferences before using them. With eagle, one “use” command and you’re good forever.
  • Learning Curve:
    • We give eagle a 6 hour time to go through a tutorial or two, and figure out how to make new components.  Chapter 17 of the eagle tutorial (on libraries) is a must read.  Kicad gets a 10 hour estimate to go through some tutorials and wrap your head around the libraries, along with getting past a few quirks. We’ve got a kicad tutorial if you’re looking.
  • Highlighting:
    • When you highlight a trace or component in eagle, it highlights in both the schematic and layout view.  In kicad, there’s no way to highlight nets in the schematic view. This makes it hard to see when things aren’t connected.  Sometimes components overlap lines in kicad schematic, but then aren’t actually connected in the netlists.
  • Undo:
    • The layout editor in kicad has no undo, except for undeleting parts. (this feature could very well be in the latest version).
  • Routing:
    • The shortcuts in kicad are great for quickly moving components and flipping between layers.  You can also “hug” traces, which lets you places traces as close as your design rules permit.  This helps to quickly make 4 lane parallel paths that zig and zag.
  • Price:
    • Non-profit: Eagle is free for 100 x 80 mm (4 x 3.2 inches) boards limited to 2 layers, non-profit. For $125 you can do up to 6 layers, 160x100mm (6 x 4 inches), also non-profit.
    • Any use: Light (100x80mm, 2 layers):$49.  Standard (6 layers, 160x100mm): $500 for schematic+layout. And there’s also pro for you 12 layer motherboard manufacturers. $1500 for everything.
    • kicad is free and open source.

Conclusion: This is by no means an exhaustive list (more experienced users please weigh in!), but our guess is that eagle would be faster for someone just starting out until you want to sell your project or make that 7in+ long pcb, in which case getting past the kicad quirks is worth the effort.

Program-o-duino = Arduino + ZIF Socket


We program boot loaders on a decent number of ATMEGAs for our roboduino kit, which involves a lot of pin bending and IC pulling. To speed up the process, Oren transformed this arduino into a program-o-duino by soldering on a ZIF(Zero Insertion Force) socket.  Now it just takes a quick pull of the lever to pop the chip in and out.

Video: How to Solder QFN MLF chips Using Hot Air without Solder Paste and Stencils

This video demonstrates how to solder a QFN or MLF chip without solder paste or stencils.  While solder paste and a stencil will product the most consistent results, this demonstration only uses an iron, flux, hot air and regular solder to get the job done.
Future videos will demonstrate how to use a solder paste syringe, as well as the recommended method of using a stencil.
Equipment used in this video:

Radio Shield Skips Commercials using RDS data

Here’s a quick demo of our new FM Radio Shield, featuring its ability to read the RDS text data off the radio stream and display it in the Arduino Serial Monitor.
The FM Shield also:

  • digitally control station, volume
  • read station strength to find good stations, or empty bands
  • head phone amplifier, uses headphone wire as antenna

The FM Radio Shield is available for purchase.

FM Radio Shield for Arduino

We’re happy to release a new FM Radio Arduino Shield that lets you listen to and control FM Radio.  With its abilit to read RDS info, the station / artist / song names can be displayed, and with a bit of code, you could have it automatically change channels when commercials play.
You can also digitally change the station, volume, and read the signal strength to find the strongest or weakest stations.  Finding weak stations could help you find a good transmission gap for your FM transmitter.
If there’s a station broadcasting traffic info via RDS, that would also be available.
FM Radio Arduino Shield

Frac Rack Version of Voice of VC Saturn Filter

A Frac Rack version of our Filter kit is now available: Voice of Saturn Voltage Controlled Filter
The VoS Voltage Controlled Filter is based around a CEM3372 filter IC (4-pole resonant low-pass filter)–the same chips found in the filters of such analog classics as the Sequential Circuits Prophet 600, Prophet T8 and Oberheim Xpander.  It features two inputs that are summed and then fed into the low-pass filter. The input and output volumes, cutoff frequency and resonance can all be controlled by VC (voltage control) or knobs.
voice of saturn vc filter

Voice of Saturn workshop and performance at BentFest2010!

BentFestival Image
On Saturday April 24th Travis Thatcher will be conducting a workshop on simple DIY electronics for music and the construction of a Voice of Saturn Synth. See more info after the jump.
The workshop entry fee is $50 and includes a barebones Voice of Saturn synth kit, as well as some materials to test out a few of the basic circuits and principles that will be demonstrated. Get your tickets here. Later that evening, at 8:30PM Travis will be performing utilizing lots of Voice of Saturn modules and other circuit bent devices. The 2010 Bent Festival will take place at 81 Front Street in Dumbo, April 22-24. See the Bent Fest website for more information. The lineup is awesome this year. Be sure not to miss our friends from Austin, Bodytronix who put on one of the craziest live acid house sets all with home-made gear!

Voice of Saturn Synth Mod

In order to get more out of your CV1 input on your VoS synth, we have come up with a simple mod that will help you do more with your synth. The mod should take only about 15 minutes and requires adding a new wire and moving an old one.


The new mod changes CV1 so that it controls the 555 that is in charge of the LFO. The control voltage adjusts the duty cycle and the frequency of the LFO, which will give you some interesting sounds. Also, if you turn up the LFO rate all the way up, the LFO will oscillate at the dominant frequency. What does this mean? Check out the video.

To do the mod. Follow the wiring guide in the picture. Remove the wires that were attached to the CV1 jack and solder them together. Then solder a wire between the CV1 jack and JP15 on the PCB. Your Voice of Saturn is then ready to go crazy with new sounds. Give it a try with the Voice of Saturn Sequencer, or even two of them!