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Technical Topics => The RF Workbench => Topic started by: Radiotech on February 28, 2022, 2102 UTC

Title: Experiments with a floating beacon
Post by: Radiotech on February 28, 2022, 2102 UTC

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.

(https://i.postimg.cc/RhKb23jZ/image.png)

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.

Title: Re: Experiments with a floating beacon
Post by: Teotwaki on March 05, 2022, 1744 UTC

Really awesome and fun idea!

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

surface drift tracker
(https://zdmkdcwjde3qmy1sxutql6lo-wpengine.netdna-ssl.com/wp-content/uploads/2019/03/15862995_web1_190307-PNR-SpongeBobCurrentTrackers456.jpg)

(https://ocean.si.edu/sites/default/files/styles/article_full_width/public/2019-02/Drifters.jpg?itok=8IxyCAqk)
(https://www.pacificgyre.com/images/microstar-gps-drifter-rendering.jpg)
(https://www.pacificgyre.com/images/Salinity%20Drifter%20Surface%20Float%20from%20Photo.png)

videos

https://youtu.be/mY2X-ZQpnvY

https://youtu.be/VRuPeDhpMMY