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My station in Panois

Posted: Sun Jan 17, 2010 12:56 am
by HeinrichH
The most stations are used to publish the measured data on the internet, mine is not designed for that purpose.
I'm using the data primary to control the climate inside our vacation house in Portugal but the data is also send to Weather Underground.

The hardware I'm using is the following:
Main weather station - Davis Vantage Pro wireless with UV and Solar
Back-up station - Oregon Scientific sensors received by RFXcom receivers, see the posted powerpoint for the rest of the system.
One RFXcom receiver LAN version for MeteoHub
One RFXcom tranceiver LAN version for HouseBot
One RFXcom tranceiver as back-up and test purposes

The OS sensors are used with Meteohub and HouseBot, this is the automation program I use to control the inside climate and to see all the graphic information generated by Meteohub, see the main page of the HouseBot remote control.
It took me a long time to get a good reception of all the sensors for Meteohub and HouseBot but with four (!) groundplane antenna's and a antenna amplifier I'm getting all the signals without problems. [file name=My_Station.zip size=0]http://www.meteohub.de/joomla/images/fb ... tation.zip[/file] Image

Re:My station in Panois

Posted: Sun Jan 17, 2010 4:33 am
by WS Grave
Henk, the zip-file can't be found!?

Re:My station in Panois

Posted: Sun Jan 17, 2010 9:24 am
by HeinrichH
Another try to upload the zipfile... [file name=My_Station.zip size=0]http://www.meteohub.de/joomla/images/fb ... tation.zip[/file]

I dont know, file size is still zero, is there a maximum file size or so? The file is about 2 MB Image

Re:My station in Panois

Posted: Sun Jan 17, 2010 9:32 am
by HeinrichH
Added some pictures... Image

Re:My station in Panois

Posted: Sun Jan 17, 2010 9:35 am
by HeinrichH
Added some pictures... Image

Re:My station in Panois

Posted: Sun Jan 17, 2010 11:24 am
by admin
Respect! That is a quite an installation.

Looks to me as if you have a radio amateur background as well ;-) When your antenna cable is RG-58 you might also think about replacing that by shorter and better cable, may be the antenna amplifier can be skipped then? just guessing...

I guess you can also control the lights in the house remotely?

Re:My station in Panois

Posted: Sun Jan 17, 2010 12:28 pm
by HeinrichH
admin wrote:Respect! That is a quite an installation.

Looks to me as if you have a radio amateur background as well ;-) When your antenna cable is RG-58 you might also think about replacing that by shorter and better cable, may be the antenna amplifier can be skipped then? just guessing...

I guess you can also control the lights in the house remotely?
Correct for somethings, my background is electronics and industrial control systems.
The reason i'm using other cable is simple, when I was starting experimenting with the reception the only cable I could find in Portugal was high quality SAT coax cable (75 Ohm) so i used that cable and terminated it with 50 Ohm terminators.
Later on when a friend of me was in Portugal with special HF measuring equipment we tried to measure the difference with the SAT cable and RG58U (Low Loss Belden cable) on both inputs and the measuring receiver tuned for 433.29 MHz, we notified that the difference was minimal so I decided to leave the SAT coax in place.

The gain of the antenna amplifier is tunable so we tuned the amplifier for maximal 433.29 MHz amplitude and minimal noise background, measured on the fourth output of the amplfier with the other three outputs connected to the RFXcom receivers so the amplifier does service as signal amplifier and signal distributor.

And another yes, I can control the lights and the de-humidifiers remote, on the moment I'm working on control the air conditioning units also remote with a USB IR controler (see http://www.usbuirt.com/), the software is ready but I have to wait to install it when I', in Portugal, running control of the airco's will be done with RFX power meters and Meteohub.

Henk Image

Re:My station in Panois

Posted: Sun Jan 17, 2010 1:15 pm
by admin
Your RF setup looks very good to me. If you consider modifying that in the future, you might have a look at sleeve antenna (similar characteristics like GP, but much easier to handle, see http://www.thiecom.de/cx425.html) and if cables do run more than 5 meter, aircell cable might be a good invest as well (http://de.wikipedia.org/wiki/Koaxialkabel, see table at the bottom)

Some user did report that using very many Oregon sensors of the same kind can have the problems that they wipe out their signals when sending at the same time. This overlap goes away after 10 minutes or so because their send intervals are not exactly the same. When using many different sensors, overlap is more statistically distributed, as sensors do have different send intervals. Did you experience problems like this?

Re:My station in Panois

Posted: Sun Jan 17, 2010 1:49 pm
by HeinrichH
admin wrote:
Some user did report that using very many Oregon sensors of the same kind can have the problems that they wipe out their signals when sending at the same time. This overlap goes away after 10 minutes or so because their send intervals are not exactly the same. When using many different sensors, overlap is more statistically distributed, as sensors do have different send intervals. Did you experience problems like this?
The overlap happens sometimes, once week I gues, the THGR810 and the UVR138 will drop sometimes because the transmit signal of those sensors is very weak and they send the data only once. The other sensors are sending the data two times or/and the signal is stronger. Thats why I positioned the antenna's near those sensors or I positioned the sensors near the antenna's if possible.

I've attached a screendump of the sensors attached to the RFXcom receiver and as you can see they are all quite right, no loss of sensors and also the signal gap of the system sensors is OK, average GAP is about 1 sec. measured over 96 hours

Henk Image

Re:My station in Panois

Posted: Sun Jan 17, 2010 7:54 pm
by skyewright
admin wrote:Some user did report that using very many Oregon sensors of the same kind can have the problems that they wipe out their signals when sending at the same time.
As you say, any pair of OS sensors using the same channel will occasionally conflict, so it's more of a problem with the old "3 channel" extra sensors (e.g. THWR288) than the new "10 channel" ones (e.g. THGR810).

Depending of relative signal strengths at the antenna, either one or both of the conflicting sensors get lost.

I'm happy to live with that situation and distribute 6x "3 channel" sensors across the channels according to highest need. At one extreme the "temp in a jar" (for estimated solar, and night time cloud) gets a channel to itself as it is very liable to frequent change. At the other extreme things like soil temp only change slowly so it's fine to crowd several sensors like that onto one channel and expect them to occasionally drop out for a few hours.