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PCARC/PF&GC building temperature via APRS

PostPosted: Thu Jan 05, 2012 9:56 pm
by KA1GJU
Once again, it's that time of year when I attempt to keep an Argent Data Systems APRS (Automatic Packet Reporting System) tracker in the building to send us (anyone for that matter) what the temperature inside the building is. Why would we want to do this? Well, there's about a hundred gallons of water stored in the pipes, toilets, well pump accumulator tank, and hot water heater. If the building were to freeze, the impending thaw would make one heck of a mess. This is why we turn OFF the well pump when nobody is using the building... especially in the winter!

How does it work?
The Argent Data Open Tracker+ is a device which 'normally' parses GPS serial data and sends out packet bursts with the callsign, present position, course, speed, and other pertinent GPS data if programmed to do so. It also has two analog to digital converters, one for measuring voltage and another for temperature. These can be urned off or on per programming as well.

SInce the building doesn't move, a fixed position can be entered when programming this little device... so no GPS receiver is actually required! Since there is a digipeater located at the clubhouse, a little QRP radio (Yaesu VX-1R HT) sends the packet of data to the digipeater about every 15 minutes, which then is sent out once by the digipeater. Home stations running APRS take the data and it gets automatically posted on to the internet for all to see. Data can be viewed (such as temperature of the building) in text form. Location of moving objects, cars, boats, aircraft, etc can be view using maps.

The callsign we are using is one you should be familar with, N1YI, and the coordinates used are actually at/near his home in Portsmouth. I did this to reduce icon clutter near the clubhouse. Since there is already an icon on the map for the digipeater and it's call, W1WQM, adding another icon and callsign ontop makes for a cluttered map...especially when fellow clubmembers drive to the club house with APRS trackers in their vehicles.


Here's the link to view the last several hours worth of data, to read the latest temp, scroll down to the last packet. The temperature is located all the way over to the right, and it is in degrees Celsius. Please bookmark it and check on it occasionally, especially when outside temps are below freezing!

http://aprs.fi/?c=raw&call=N1YI

Here's an example of the above link:

2012-01-05 18:17:39 EST: N1YI>APOTC1,W1WQM,WIDE2*,qAR,W1TG-1:!4305.62N/07046.44W- 12.7V 13C = PF&G temp
2012-01-05 18:32:39 EST: N1YI>APOTC1,W1WQM,WIDE2*,qAR,W1TG-1:!4305.62N/07046.44W- 12.6V 13C = PF&G temp
2012-01-05 18:47:40 EST: N1YI>APOTC1,W1WQM,WIDE2*,qAR,W1TG-1:!4305.62N/07046.44W- 12.5V 11C = PF&G temp
2012-01-05 19:02:41 EST: N1YI>APOTC1,W1WQM,WIDE2*,qAR,W1TG-1:!4305.62N/07046.44W- 12.4V 11C = PF&G temp
2012-01-05 19:17:42 EST: N1YI>APOTC1,W1WQM,WIDE2*,qAR,W1TG-1:!4305.62N/07046.44W- 12.9V 13C = PF&G temp
2012-01-05 19:32:42 EST: N1YI>APOTC1,W1WQM,WIDE2*,qAR,W1TG-1:!4305.62N/07046.44W- 12.6V 13C = PF&G temp

When the temp falls below 7C or 45F the following is sent, and the rate changes to every 10 minutes:

2012-01-03 07:01:30 EST: N1YI>APOTC1,W1WQM,WIDE2*,qAR,W1TG-1:!4305.62N/07046.44W- 06.6V 6C = LOW TEMP ALARM T<7C or 45F!
2012-01-03 07:11:39 EST: N1YI>APOTC1,W1WQM,WIDE2*,qAR,W1TG-1:!4305.62N/07046.44W- 06.6V 6C = LOW TEMP ALARM T<7C or 45F!
2012-01-03 07:21:54 EST: N1YI>APOTC1,W1WQM,WIDE2*,qAR,W1TG-1:!4305.62N/07046.44W- 06.6V 5C = LOW TEMP ALARM T<7C or 45F!


If you see this warning several times in a row (not a fluke or glitch), then the heat is OFF and needs to be corrected. Contact Duece, N1YI, via cell at 603-231-1392, work 603-474-5166 or me Kriss, KA1GJU, at cell 603-557-7121 or home 603-772-2779. If those don't work, get on the 2M radio and ask around!

Notice the low battery voltage too, 6.6V, because somebody unplugged the wallwart and the building monitor was running off 6 AA batteries, which were near dead. The battery pack was required due to the radio not having a mechanical on/off switch, it's software controlled... so if there was a power interruption, the radio would have to be MANUALLY turned on. Since PCARC/PF&GC building is at the end of the power line, glitches happen!

Now if you want to see ALL APRS activity in the area on a map view, try this link:

http://aprs.fi/?addr=Greenland%2CNH&mt= ... _s=ss_addr

Large ships with AIS (See: http://en.wikipedia.org/wiki/Automatic_Identification_System) can often be seen in Portsmouth Harbor as well. This separate locating system gets piped into the APRS servers via the web. Change location to Miami, FL or some other large shipping port and watch the boats!


So... any questions or if you want to learn more about this mode of Amateur Radio, give me a shout on radio, email, or phone.
73 de Kriss KA1GJU-X Where X=Int(9) :lol: