51.2c !!

[KetteringUK]

I think my weather station is having a few glitches after over 5 years of service. Every now and again I get a reading showing 51.2c for the temp, and variations on numerous other readings. Usually it's just temp but think the pressure and wind have shown odds too (need to monitor those)

http://grid1.co.uk/weather
"Highest Temperature 51.2 °C at 09:13 on 26 March 2015"

I think for the sake of £15 I might change the temp unit but can anyone confirm how the base station copes with this? Just to check how does the station know which sensor to talk to if there is another station nearby?

Thanks
Graham

[logjam]

I have this problem with a neighbours unit. The console has no way of knowing which sensor unit is which. Basically it latches onto the first one it finds, and then listens out for the regular data coming from that unit. To make sure the console is getting the right data, place the sensor unit right next to the console. The console should update at the same time as the sensor LED flashes. If the console updates at any other time, then it is receiving data from another unit. In the unlikely situation where both stations transmit their data very close together I temporarily disconnect the wind unit from my sensor unit. When the console starts to show data if there is wind data I know its not my unit. Naturally this only works if there is wind blowing.

I have evidence which suggests that the sensor units of each station can transmit its data a tiny fraction of a second fast or slow. This means that a second unit's broadcast can very slowly catch up with your own, leading to interference and loss of contact as both transmit together. If that happens then the sensor console has to be reset to broadcast at a different time.

[AllyCat]

Hi Graham,

I think for the sake of £15 I might change the temp unit but can anyone confirm how the base station copes with this?

If you currently have a 5 year old "Maplin" station, then I can say with some confidence that the "spare" Temp/Humidity sensor which they now sell will NOT work with your Console. The manufacturer (Fine Offset) changed the "wireless protocol" (not the radio frequency, but the "language" that the station talks) about 3 years ago. Sorry, but if the transmitter is actually "broken" then I can only recommend buying a complete new station (when next "on offer").

However, you may just have an issue with poor radio communications (or perhaps interference) so I suggest that you test/replace the transmitter batteries and try physically "moving things around a bit" to see if the comms can be improved.
_____

The FO transmitters do report an "address" (perhaps better called a "signature") but this changes when the batteries are replaced (unless done very quickly between transmissions). Also, the Console looks not only for this address but also switches on for only about one second in each 48 (to save battery power), when a signal is expected. However, note that many devices of this type (wireless central heating thermostats, car alarms, doorbells, etc.) all use the same radio frequency, so "blocking" can be very common. That's probably why FO use a 48 seconds period instead of the more common 1 minute. But the high timing accuracy of FO stations does mean that one can block the signals from another for perhaps a day or more.

Re-synchronisation normally requires the Console to be powered-down (remove batteries), but the later non-touchsceen FO stations are better because they can be resynchronised by simply holding in their <down-arrow> button for ten seconds.

Cheers, Alan.

[KetteringUK]

Thanks for the advice. It's definitely an odd intermittent error as nothing has moved physically in the last few years and the batteries are replaced frequently to avoid disconnections. I have tried normal batteries instead of rechargeable too but no difference. It seems to be fairly stable at the moment, just one or two errors every other week.

Given the numbers are always obvious and consistent (Temp 51.2c Wind 117mph), I just edit the files when I see them and will carry on until either it breaks or great offer appears.

Thanks
Graham