www.shaneburrell.com BLOG Search – Rescue – Scuba – Diving – Telecom – Electronics – HAM Radio

17Feb/150

KiCad Librarian on OSX MAC

Screenshot 2015-02-17 16.27.23This tool comes in handy for organizing kicad footprints and modules.  Unfortually it doesn't build on osx normally.   I have created a homebrew repo and after ignoring some build errors it seems to compile and work great on OSX.

The main site for the tool is at http://www.compuphase.com/electronics/kicadlibrarian_en.htm.

My homebrew repo is located at https://github.com/shaneburrell/homebrew-kicadlibrarian

 

17Feb/150

OpenSource HT Part 2.

Prototype boards for testing the RF module along with provisions for a low pass filter have been sent off for manufacture.  I'm expecting to see these back in a few weeks.  In the meantime below are links to the Gerbers for the test board as well as Kicad Modules for making your own boards that use the DRA818V module.

DRV818V Image

 

DRV818KICAD

DRV818ProtoBoard

13Feb/150

OpenSource HT Part 1.

I've been looking at migrating some of the work I've done on my ComboStar build to VHF/UHF including GSMK and Codec2.  With 3D printed case, lithium battery, STM32F405, DRA818V/U, and a nice OLED screen I think its possible to build a DIY 1 Watt radio that support analog, FSK (APRS), and Codec2 GSMK.  I already have several working STM32 projects with successfully generating various modulations including GMSK, POCSAG and AFSK.  My first step is to play with the DRV818V module and see how difficult it is to implement.  From the datasheet I've included a low pass filter in this prototype which I should be able to prototype with my existing STM project board.

SBDHT

15Jan/150

Yosemite Encryption Paused Issue Macbook Pro

After trying many of the suggestions online about fixing this issue I figured out the quickest way to recover.

1. Do a unencrypted Time Machine Backup

2. Goto recovery mode and completely format the startup drive and set for normal (non encrypted) journaled file system.

3. Restore backup

Thats it the quickest way to resolve the issue without completely reinstalling.

Filed under: Hacks, Stories No Comments
6Mar/140

First Release of Rescue Calculator

https://itunes.apple.com/us/app/rescuecalculator/id829130203?ls=1&mt=8

Filed under: Rescue No Comments
3Mar/140

First Release of Rescue Score.

Rescue Score is used to monitor and record forces during rescue and other patient movement during training.  Replacement for the cup of water method during vehicle extrication.
RescueScore - Download from the AppStore

Filed under: Rescue No Comments
10Sep/130

First successful Combostar w/STM32 Codec 2 test.

It has taken almost 2 years but I finally did a local test on 30 Meters of the modified combo-star radio with a STM32F4 based digital codec board running the last port I could find of Codec2. There is still a lot of work to be done packaging, winding the rest of the filters, and completion of the high power sections. Must of the time was spent on independent projects and assembly of the combo-star was quite a undertaking.  Although a hacked combo-star which I'm sure most of them are in the end given the home brew nature, I've got something now I can work with that is all integrated.  Eventually I'll even have it in a ready to go box.

Filed under: Hacks, KiCad No Comments
8Jul/130

ComboStar Build

I've started work on my ComboStar HF DSP based radio. Overall with a few hard to find parts, it's a great project to build. Assembly has been easy with a large selection of alternate parts on on the board. The BOM and schematic kept confusion thus far to a minimum. Big thanks to W4ZCB and SP5TAA for sending critical parts (Crystals and EEPROM). Mouser does sell a 16.67mhz but not in the package provided on the board. Thus far I have the DSP booting and awaiting more parts to complete the build. I completing my build with 805 size parts and hot air aides in getting everything straight. There are a few 603 exceptions such as LED's and in a few places I used 603's with parts I had laying around.

I've done about 98% of the board using mouser for parts sourcing. RFParts has the filter. Several members of homebrewradio provided critical crystals and EEPROM. Kitsandparts has magnetics and wire. The only items that were hard to come by seems to be the mini-circuits parts. I found a close match that pulse manufactures that I will try in place of the MCL 4:1 part (This likely won't work and W4ZCB was kind enough to send me an alternate). I was able to locate the amp on Ebay in small quantities. I've been assembling as parts arrive and testing voltage prior to setting any major components. So far so good and only a few mistakes that were easy fixes with hot air assistance.


DSP Testing the ComboStar.  This is the first step in testing and be sure to check voltages prior to placing anything expensive.  Also on the DSP be very careful as the pins are fragile.  The technique I used was flux first, then tack a pad placing the part where you want it. You have to use very light pressure with iron to prevent bending pins.  Ensure you have no burrs on the tip prior.  If you evenly apply solder as you go down each row of pins you won't have to wick any excess.  I've found that a continuous motion leading a bead of solder over the work does well with no or little cleanup.

More progress and DSP section is loading with Blinking LED.  Just as a note for troubleshooting - No LED check LED orientation (You should have check voltages prior to DSP soldering).  Solid LED - Check pF on crystal. Likely not enough capacitance = lazy clock.  I used 22pF.  Also for clarification to power DSP attach to DSP section and install jumper.


The OCXO section was tested and a nice clean output is seen. Any OCXO could be used in theory. The DDS input reference is 400mhz max and the IC has a 4x-20x multiplier. The schematics are for a 3.3v OCXO but this could easily be modified to work with several units. Assembly was straightforward but a heat-sink had to be made to fit in the board space. I drilled and tapped a hole to allow the heat-sink to sit off the board to stay clear of the components for the regulator underneath. A heat-sink is required as this part gets very hot. With the heat-sink shown the temps get warm to the touch but dissipation is well within the 317's spec.

 

Various Photos during the build.

IMG_0807

19Mar/130

KICAD on Mac OSX – The easy way.

If you have trouble getting KICAD to build and haven't checked out homebrew you might want to check it out. I try to keep a current tap for KICAD.

To install first install homebrew if you haven't already:

ruby -e "$(curl -fsSL https://raw.github.com/mxcl/homebrew/go)"

Then tap the KICAD homebrew script to build.

brew tap shaneburrell/homebrew-kicad
brew install kicad

To update/upgrade to the latest KICAD as often as you like.

brew update
brew upgrade
Filed under: KiCad No Comments
14Mar/130

KICAD Mac OSX Build – BZR 4002

KICAD Board

I found it difficult to find a current build of KICAD for OSX.  Below is a build that works with current OSX.  Just unzip into Applications and start KICAD.  If there is interest I may do more frequent builds.

 

KICAD-BZR-4002

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