I’m slowly working towards doing some experiments with mesh networking (OLSR) and Icom ID-1 D-star Radios in Digital Data mode.  I’ve been wondering what coverage I would (should) see from a vehicle, back to one of the locations where I have an ID-1 in a fixed location (thanks EI3JB/EI8JA).

I got back from a trip today, grabbed an ID-1, an Omni Antenna, Laptop, a short bash script I wrote to ping and record replies along with a GPS position, and an old GPS-18 puck.   All the nodes have fixed IP addresses so the script is quite simple, ping host A, if A replies within 2 seconds, record the next position output from the GPS, try the same with host B, loop forever, nothing fancy or terribly accurate.

As I only have two nodes set-up, and without much preparation (shutting down chatty applications), I persuaded SWMBO to do a short (war)drive, while I kept an eye on the laptop.

This first picture below shows (the red dots) the coverage from Nicky, EI3JB’s place (roughly at the 8 in the R708 closest to the top). Note the few packets recorded in Tramore, shortly after I left my own place.

The second is obviously from my place, as it is much more centred on Tramore.

Nothing really ground-breaking in either picture, but useful to help visualise potential coverage nonetheless. There is a huge black-spot on the section of road just leaving Tramore, as far as Ballykinsella (L4061 on the map).  This is of no surprise, as it is a tough location  for 430Mhz signals to get out of. What was surprising though is the packets received from EI3JBs location out in Tramore.

Next steps are to get EI8JA up and running, and complete a more thorough survey.

Now though, it is time for a beer!

I’m not long back from the DCC, and I thought I would comment on it while the memory is still fresh. I had never been before, so I was wondering what I had let myself in for. Well I have to say I had a blast. From my accidental meeting of Larry WR1B on the shuttle to the hotel, to having lunch with the TAPR folks just before I caught my flight home, the atmosphere at the event was all about the sharing of knowledge. Like all good events, most of the really good discussion goes on in the corridors between presentations. Over breakfast, lunch, or indeed in the demo room.

Coolest presentation for me was the HPSDR, Modular Software Defined Radio, and the sheer enthusiasm of the guys was infectious (I want one!).

The picture below shows the set-up (belonging to N8ZM I think) for the tutorial on Sunday morning.  The intention was to monitor the transmitted waveform from the transmit side on the spectrum analyser (large box to the right of picture) and also to receive and decode transmitted signals from Larry WR1B’s recently constructed NEU-PSK (small flat black box). All great fun.

I may not make it next year, or indeed the year after, but I will make it back.