DSTAR Hotspot

I’ve done some experimentation in the past with a DVAP DSTAR Hotspot running on a Raspberry Pi.  Prior to my latest vacation in the Gatlinburg, TN area, I wanted to play around with another setup.  I borrowed a hotspot setup still based around the Raspberry Pi, but using the DV Mega Board instead of the DVAP.  This is a much cleaner installation as it doesn’t have the extra cables, etc., that come along with the DVAP.

The one thing that is missing for either setup is a nice case to keep it all contained and neat.  A fellow ham in TN, turned me on to Hardened Power Systems who makes a 3D printed case for a DSTAR Hotspot using either the DV Mega Board or the DVAP USB Adapter.  They call it the DHAP or Digital Ham Access Point.  Note that the link I provided goes to the DV Mega version.  If you have a DVAP, make sure and order the proper one.

Noticing that the company was in TN, I reached out with hopes to be able to pick on up in person, but alas they were ~2 hours away from Gatlinburg.  After talking to them, they said I could order one online and have it in a couple of days so well before I left.  An important note, the DHAP is designed for use with the Raspberry Pi B+ or the Raspberry Pi 2.  It does not work with the original A or B models, which of course is what I had on the trip.  Enter Amazon Prime and I had a new Pi 2 the next day well ahead of the arrival of my DHAP.

The DHAP has a DC/DC Buck Convertor in it able to take input voltages from 5VDC to 36VDC and also includes a built in battery case for four 18650 LiPo cells.  There is no transition between power options so plugging in an external power supply cuts the batteries.  The batteries must be removed and charged external to the DHAP.  I ran on two LiPo batteries for a few hours before they went dead.  Obviously your mileage may vary given TX duty cycle, etc.

Here are some pictures of my setup utilizing the single band (70 cm) DV Mega Board:

dhap-1 dhap-2a dhap-2 dhap-3

I’ve followed 3D printing with mild interest, but obviously wondered what one could seriously do with it.  The folks at Hardened Power Systems have showed me exactly what some good engineering can turn out.

As these are 3D printed and very rugged, the finer parts are a bit brittle due to the 3D printing process.  I ended up stripping out one of the screw holes that anchors the Pi to the case and there is a small piece of printed plastic that serves as a wire guide which I snapped off accidentally as well.  I was being careful and not torquing things down, etc., and still had these minor issues.  Perhaps in time, the product will evolve and reduce the possibilities of incidents like I had.  The have already evolved to use rare earth magnets as a closer mechanism vs. plastic tabs on the earlier versions.

The one thing that I really felt was missing from the package was a 90 degree SMA adapter, which I obtained from Amazon for ~$5.

The DHAP sells for $99 and is available direct or from GigaParts.  In fact, the latter sells complete DHAP setups including the DV Mega Board and Pi.  It is a really nice setup especially if you plan to travel with your hotspot.