HAMNET and link planner for point-to-point links
HAMNET is a data network run by radio amateurs using WLAN technology on amateur frequencies, independent of the internet. In Austria ÖVSV members have operated it since 2005; links connect all federal states. The Signal-Pirat link planner calculates your own point-to-point link.
Open in the browser
No installation, no sign-up needed.
What the page does
- User access mainly in the 13 cm band, links between nodes in the 6, 9 and 13 cm bands
- Received level and margin from power, antenna gain and cable loss
- First Fresnel zone at mid-path and the 60 % rule
- Earth bulge and radio horizon from antenna heights
- Warning for too little margin or a link beyond the radio horizon
Background
Line of sight alone is not enough for a stable link: at least 60 per cent of the first Fresnel zone should be clear of obstacles. At 5.8 GHz over ten kilometres the first Fresnel zone has a radius of a little over eleven metres at mid-path. Earth bulge adds to the required antenna height on longer links. WLAN sensitivity depends strongly on the data rate; higher rates need more level. Transmitting requires an amateur radio licence.
In practice
How it works: enter frequency, distance, transmit power, antenna gain and cable loss per side, plus the equipment's sensitivity at the desired data rate and both antenna heights. The planner shows whether the margin suffices and how much of the Fresnel zone must be clear.
Frequently asked questions
Do I need a licence for HAMNET?
Yes. Transmitting on amateur frequencies requires an amateur radio licence.
Where is the nearest access point?
On the node map (hamnetdb.net) and in the ÖVSV wiki.