Experiments with a floating beacon

[Radiotech]

I was insipred by the fish net beacons, and thought about trying to build one my self. A indoor plumbing pipe fits the D-cell batteries really well. I printed out an end cap and a holder for a RF transmitter. Since a solar cell is hard to fit to the beacon, low power consumption is very important.

A Attiny45 has about 2-3mA of power draw, that gives about 6-8 months on a D-cell battery. I get 6 volts from 4 batteries, and can use a small DC step upp regulator to get a bit more power out. The DC step up adapter does how ever require 5 volts(and my batteries will be down on 4 volts during the last 25% of their life), and it has a idle current that draws energy from the battery.



Either i will fit the TX inside the pipe, or build a small head on it for more room. The pipe is Polypropylene plastic, its hard to glue and paint, but cheap and easy to work with. I looked for PVC piping, but couldnt find any in the same diameter. Most of the parts will halfto be press-fitt. I plan to have a floating collar at 80% of the length, and a short whip antenna.

[Teotwaki]

Really awesome and fun idea!

For build ideas you can look at existing ocean buoy trackers such as these

surface drift tracker






videos

https://youtu.be/mY2X-ZQpnvY

https://youtu.be/VRuPeDhpMMY