I\’ll admit it, I\’ve drank the Anderson Powerpole kool-aid. I like them. I like the detent. I really like the fact that they are genderless. I like the fact that lots of other ham radio people use them. I\’m not that crazy about having only one supplier of them. However, it looks like their is another alternative. Tyco/AMP has its Power Series connectors that seem very similar to Powerpoles. I\’ve picked up a few to see if they are interchangeable. One thing that I have not seen from them is PCB mount contacts. Anderson does make those in 25 A and 45 A varieties.Continue reading
ATX Power Supply Breakout Board
How many of you have or know of someone who has an old computer just sitting in the closet gathering dust. How many of you would like to have a multiple output bench power supply? Do you need an extra +12V DC power supply for your CB, ham shack or office? What we have here is a 4\” x 6.3\” PCB that has all the standard connectors needed to take the output connectors from an ATX power supply and give you easy access to them.Continue reading
The Dirty Truth about USB device Charging
How many devices do you have that charge over USB? How many devices require you to do something special, or have a special adapter to do it?
The last few cell phones I\’ve had have USB micro or mini ports to charge from. I figure I can take a USB A Male to USB micro/mini Male cable and just plug it into a USB port and get power… except that doesn\’t work some times. Then there are the Apple devices. You\’ve got your iPods, iPhones and iPads. They do their own thing as well. What\’s a geek to do?Continue reading
Automated Setup of Subversion Repository
I may be unique in this respect, but I like to keep individual subversion repositories for each project. To make life a little easier in setting up the repository, I have a handy little bash script that sets up the repository with the /branch /trunk and /tags directories. Continue reading
Downsampling PDFs to save space
One of the best things since sliced bread, IMHO, is automatic scan to email/pdf functionality on the multi-function copier/printer/scanner/fax. This makes copying print articles easy so that you can send them to friends, or keep an article out of something you borrowed. My personal philosophy is \”scan once, process as needed.\” That means I scan at a high resolution, and go from there.
Now, say you want to share that article, whatever with your friend… and that high-res PDF is too big to email… or they have a slow net connection… you get the idea. How do you shrink the PDF easily? Ghostscript is part of the answer. The other part is, write a script. What we have below is a script that takes multiple input files and runs each of them through ghostscript with its screen settings and outputs it with _small at the end of the base filename. Most of the logic in the script is just for parsing the file name and path to get the extension of the base filename in the right place.Continue reading
Concatenating IEEE E-Book PDFs
For those of you who are IEEE members, they now offer some of their \”classic\” ebooks as a free download off IEEE Xplore. The only problem is that they come in multi-part PDF files and are not named in a rational fashion. So… if you have linux, pdftk installed, and a mass download extension on your web browser, (such as the great Download-them-All for firefox) we can fix that.
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Setting up an IAR Project using the TI MSP430 and SimpliciTI
Many of you know the possibilities that ultra-low power devices open up. One thing TI has done to make things even lower power is to craft their own \”lite\” protocol, SimpliciTI. You even get nice, examples for use when you install the protocol dev files. Now, what happens when you want to do something more than just compile the examples, good luck. Exactly what you need to add to the project is left as an exercise to the coder (you). This walk-thru is for using SimpliciTI with the ez430-RF2500 kit. Changing it for one of the other processors should not be hard, but I don\’t work with them.
The first thing is to make sure that you have the correct version of IAR. If you get the kickstart version off of IAR\’s web site, it will not allow you to link the projects because of the code size limitation (4k). You can get a 30 day unlimited trial from IAR. This example uses IAR Embedded Workbench version 4.20.1 and SimpliciTI v1.1.0.
Altium Designer Overbar or Overline
While trying to move to a new EDA package, Altium Designer, I had a really hard time finding out how to put a overbar, or overline on top of a pin designator. This is usually used for active low signals. In Eagle PCB you just put an exclamation in front of the signal, or around the part to have the overline, like !RST or !TST!/GPO. For Altium Designer, each letter that needs an overline should be suffixed with a backslash, e.g. R\\S\\T\\. You\’ll never find it in the Designer notes unless you know to look for backslash. The words overbar or overline are nowhere to be found. I hope that this saves someone some time!
Encrypted, remote backup
So, I\’m a big fan of backups. I\’m a bigger fan of differential backups. My personal favorite method of doing them is using the rdiff-backup script on a linux box. What happens when you have sensitive information that you need to remotely backup. Do you upload a new encrypted file of everything every night? Do you have to download the whole file to get to one file? If you were using an encrypted tarball or sometype of encrypted loopback file, like truecrypt, then the answer would be yes. That is bad if you have a slow link. One way to solve that is to do encryption on each file. To do this we can use EncFS and sshfs. Both of these are in the default repositories for the current ubuntu versions.
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