[aprssig] APRS = the IoT of Amateur Radio [was: APRS to the planet rescue?

[Steve Dimse]

> On Apr 11, 2017, at 8:06 PM, Scott Miller <scott at opentrac.org> wrote:
> 
> I remember seeing an APRS flood monitor at Dayton a few years ago.  They weren't particularly cheap devices, but I think they used ultrasonic gauges.  A simple float switch would do it.

The device is Flood Advisor

http://floodadvisor.com/products.php

It was quite power efficient, mine ran for two years on a single 6 volt lantern battery, sending the tide level every 5 minutes. findU has support for the graphing format, and can give excursion from predicted tides.

I hope if you do develop your system you will consider including support for an ultrasound module. These are available for about $7 on EBay

http://www.ebay.com/itm/Ultrasonic-Module-Distance-Measuring-Transducer-Sensor-Waterproof-/201322915390?hash=item2edfc7e63e:g:DvcAAOSwYIxX9eS8

The interface is easy, pulse one pin to trigger, measure the width of the returned pulse on another pin, and do a little math.

With the float switch you do not know the device is functional unless it is triggered, and then you do not get any info about the level other than that it is above a certain point. US provides proof the device is correctly working, allows you to follow rising and falling floodwaters, and makes tidal measurement practical.

Steve K4HG