I thought that the test was pretty easy; at least we're no longer required to learn Morse code. I did download the documents
that had every single question in them and read through them (they were big--the one for the General test was 97 pages long) studying the questions. No, you can't just memorize "hey, that one's answer was C" because in the real test they mix up the answers a bit--you need to memorize what the answer actually is out of the choices. Still, I think that just about anyone could pass at least the Tech exam just from a couple of days of study.
As for the hardware....
It is quite possible that I'm having too much fun working on this.
I've already investigated hooking the server up to noam.aprs2.net to receive updates, that part is going to be pretty easy.
I've found that there are at least 3 Ham operators out there that already have geiger counters reporting over aprs for their own use.Here's one of them
, he's using an arduino with custom code and a TNC-capable radio. He's also reporting Temperature, Humidity and Dew Point.
There are two packet types in use to report radiation counts (and the one above actually sends both, at different intervals): as a weather report and as Telemetry. (Actually, the one above is the only one I found using a weather packet). Added bonus is that we'll be able to use aprs.fi/telemetry to view charts for sites reporting over aprs.
Our initial version is going to be using Telemetry packets I think unless someone has a really good reason we should use the weather packet. I'm open to suggestions on this point.
After some wrestling with alsa, snd-usb-audio, and asound.conf I now have my Pi receiving APRS packets from the radio using a usb soundcard (The one I have working is this one)
. This way you don't need a TNC-capable radio, you can use the $30 LCR. We're going to have to be carefull about self-interference, the radio doesn't receive too well from inside my computer room. I ended up having to lay the radio on it's side to receive packets (I think the rubber duck antenna that comes with these are circularly polarized)