Between July 16th and July 23rd 2016, the annual YOTA summer camp took place in Wagrain, Austria. During this summer camp, participants were educated about our hobby, manned the shack and got to know each other during the many activities. One of the most interesting classes for me was about HAMNET.
HAMNET (also known as AMPRnet) is part of the internet that is operated by Amateur Radio operators.
Since its allocation to Amateur Radio in the mid-1980’s, Internet network 44 (220.127.116.11/8), known as the AMPRNet™, has been used by amateur radio operators to conduct scientific research and to experiment with digital communications over radio with a goal of advancing the state of the art of Amateur Radio networking, and to educate amateur radio operators in these techniques.
Within this /8 network that is announced by USDC in America, which consists of 16.7 Million IP addresses, every country can request their own /16 subnet. For Belgium, this is 18.104.22.168/16. This subnet can then be distributed across the users inside that country, provided that the country has the means to announce the /16 themselves.
The hotel we stayed in had been completely taken over by UTP and coax cables. Every room had its own Routerboard to allow the WiFi networks to be distributed. One of these networks was HAMNET, distributing 44-ip’s to the participants. The HAMNET uplink was a 5GHz point-to-point from the local repeater site on the top of the valley.
One one of the final days of the summer camp, we were planning to visit one of the mountains of the valley our hotel was located. As we’d learned about HAMNET and routing it on Mikrotik hardware the day before, I thought this would be the excellent opportunity to put everything we learned to the test.
Around midnight we assembled a small antenna mast to hold the 5GHz Mikrotik GrooveA-52HPn with a directional panel antenna aimed to the top of the mountain we planned to visit 8 hours later.
All packed up with two Groove’s, a panel antenna to link back to the hotel, an omnidirectional antenna to serve as AP for the participants on top of the mountain, a Routerboard to connect and power everything and the necessary batteries, we headed up the mountain.
After unpacking everything at the top, we started to scan for any signals of the PTP-AP located back at the hotel. After a lot of trying and relocating to an even higher point, we had no luck. At that moment, one of the teamleaders who had not joined us to the top of the mountain radio’d in that the hotel, and what it seemed the rest of the village, was suffering from a power outage. Of course, this explained why we could not get any link with the hotel.
We attempted to link directly to the repeater site at the other side of the valley, where the hotel was getting its internet from, but due to being located at the wrong angle of the antenna, we had no luck either.
Defeated, we drank a beer before heading back down.
I guess Murphy’s law always finds a way…