Topic: Tower Sensor does Temp, Hum, and Pressure?

[tom95521]

New to acurite products. I bought a 5n1 from Costco and signed up to myacurite.com and I noticed that my outdoor sensor (06002RM/592TXR) is reading pressure along with temp and humidity. I was not expecting pressure. It seems to be slightly different readings than my 5n1 sensor. Does the tower sensor have a barometer?

[nincehelser]

New to acurite products. I bought a 5n1 from Costco and signed up to myacurite.com and I noticed that my outdoor sensor (06002RM/592TXR) is reading pressure along with temp and humidity. I was not expecting pressure. It seems to be slightly different readings than my 5n1 sensor. Does the tower sensor have a barometer?

No.  The tower sensor does not have a barometer.  The barometer is in the bridge/SmartHUB.

Your 5n1 doesn't have a baro sensor, either.  It's actually in the display.  Every Acurite display has its own.  That's one reason you'll notice differences.

In the original MBW protocol, the 13 raw barometric parameters were sent from a baro sensor in the bridge in a separate http statement.   This was because the firmware did not have the math code to process the baro information, so it handed everything off the the MBW servers for further processing.  This was scheduled to happen every minute.

This changed in the myAcurite protocol.  The firmware in the bridge was updated to be a "SmartHUB".  It now has the ability to process the raw baro parameters into a single number representing either station or altimeter pressure.

This cut out a whole line of http messaging in the new protocol.  However, the barometer value still needed to be sent, so it was just tacked on to the other http messages from the other sensors.

[tom95521]

Thanks. I didn't realize the display transmitted data to the smarthub. I thought the display was just a receiver.

The sensors must have some sort of cdma collision detection so they can transmit on the same channel without data corruption. Do you know if there is a checksum/crc on the data stream packets? Sometimes some of my charted values are strange or drop out (like wind chill).

[nincehelser]

Thanks. I didn't realize the display transmitted data to the smarthub. I thought the display was just a receiver.

The sensors must have some sort of cdma collision detection so they can transmit on the same channel without data corruption. Do you know if there is a checksum/crc on the data stream packets? Sometimes some of my charted values are strange or drop out (like wind chill).

The displays don't transmit to the smartHUB.  They are receive-only.

There's no collision management system on the radio side.  The sensors are simple transmitters only. The best they can do is transmit their data periodically and hope.  Each sensor transmits on its own particular schedule.  For example, most tower sensors transmit every 16 seconds.  Some 30 seconds.  Other's a minute.  A 5n1 transmits every 18 seconds.

Then, of course, there are all sort of other devices also using the 433MHz frequency at the same time.  Security systems, car key fobs, etc. etc.    Some ham radio operators also operate in that band.  It can get kind of crowded in some areas.

As far as the structure of the radio packets, I know little detail there.  You might look into the RTL_433 project for more information and pointers on that kind of thing.

[tom95521]

Thanks. I missed the part where you said the barometer in the smartHUB is the one that is uploaded to myacurite/AWS. I also bought a lightning/temp/hum sensor but I guess I can't use it with my existing weather display or smartHUB (firmware upgrade?). All this stuff is confusing but interesting at the same time.

[nincehelser]

Thanks. I missed the part where you said the barometer in the smartHUB is the one that is uploaded to myacurite/AWS. I also bought a lightning/temp/hum sensor but I guess I can't use it with my existing weather display or smartHUB (firmware upgrade?). All this stuff is confusing but interesting at the same time.

For the new lightning sensor, you need a compatible display.  There's one for the 5n1 coming out later this month.

As for the SmartHUB and myAcurite being compatible with the lightning sensor you'll just need to wait on that.  I suspect they'll get to it after the migration is complete this month.