70003 discontinued, replaced by 80002

[admin]

Bert from rfxcom gave me the following information on the new line of rfxcom revceivers that replace the 70003 we have used for Meteohub so far.

Hi Boris,

The receiver module in the 80002 is equal to the module in the 70003.
The differences are:
1) The enclosure and the PCB are larger which makes it easier to access the
receiver modules.
2) The antenna has changes from a groundplane to a telescopic antenna.
3) The antenna cable is no longer used
4) The antenna connector has changed from F-conn to a BNC connector.

The newest firmware version 24 with changes for the xxx918 sensors is now
delivered.

[skyewright]

The newest firmware version 24 with changes for the xxx918 sensors is now delivered.

Just thought I'd mention that I got the v24 firmware upgrade for my 70003 and the xxx918 sensors are now being picked up really well. :cheer:

[admin]

I have just received updated receiver modules from Bert and a LAN based rfxcom. The new ones come with a telescope antenna that is much more handy than the ground plane antenna.

[binbags]

Hi Boris

I have just ordered the rfxcom insert master receiver 40071, this saves sending back to rfxcom and comes with the new firmware. All I have to do is place this receiver module in place of the other one.

Should I wish to change the antenna later on, I will do, but the ground plane is OK for me.

[J.S.]

Great you now can pick up the sensors, SKye, what is the distance between RFXCOM and the O.S. sensors?

[binbags]

Hi

Distance is about 20 metres, I still have the aerial that came with 7003 unit, so it sits in the loft next to the gable end.

I sometimes pick up other peoples sensors as well, although I do not know how far away they are.

regards

alan

[J.S.]

Well, I asked Skye because the change in firmware had a good effect.

But your answer is much appreciated! It seems to be extremely difficult to get people to say what the maximum distance is they can reach. For most, it is probably not a big deal but I can get my stations well into the country if I like, so distance is important. People could say: "30 m through 5 brick walls" or things like that. But apart from you and Skye, nobody answers. Not in this forum, not on RFXCOM forum and not their techstaff...They refuse to give any indication. I am a bit irritated, because if you work wireless it seems to be very important to know what the distance is. Oregon gives distances, Davis does. I do understand that RFXCOM depends on which sensor you choose (some are indicated for 30 m others for 100m).

So you measure at 20 metres. But what is the maximum distance (through a couple of walls or line of sight)? Did yiou test it or can you tell me what your exact situation is??

Thanks in advance!

[binbags]

Hi
Not easy for me to answer this one, I think you would need to know the power output of your sensor and the sensitivity of the rfxcom and the gain of the aerial, this needs specialist equipment, such as a spectrum analyzers.

All these units are very low power. The sensors should be in milliwatts and the rfxcom rec,vr in milli or micro volts. The sensors will still transmit at there designed power output and be attenuated by walls, trees and distance, etc.

If your sensor was pushing out say 5watts, then yes this would be received over a greater distance and the rfxcom would not need anything other than a directional aerial to get the best from it, but you also have to take into account other interference to the rfxcom unit, all this will increase with distance. I am not sure but 432mhz might not be a long distance transmission frequency in some countries and at increased power levels, it would be a no-no.

[J.S.]

Thanks! I do not think 433 Mhz hampers it (well, not to reach over 200 m for instance). Skye has received a neighbours Oregon Scientific sensor (rain or wind I thought) 900 m away. At times. this was in a line of site. Just to demstrate that, in a line of site it seems like the RFXCOM is capable of long distances.
Another point it the Superhet 302 receiver, which als works at 433 Mhz and is regularly built in Nexus/Mebus/ Irox/Cresta stations. This unit can receive up to 1000 m accoring to the maker of this receiver.

Point is: how much does wall restrict these distances? If a standard OS WMR 100/200 is designed to receive over 100 m in line of sight and 50 m with a or some walls between it, can you say that the RFXCOM will do a lot better or not??

I understand the dificulty. Will buy it anyway, that is for sure. I'll figure something out.

Thanks again for your help!

[skyewright]

Skye has received a neighbours Oregon Scientific sensor (rain or wind I thought) 900 m away.

Err, 500m?

*** Later EDIT: My recall was wrong - it really is 900m. So far I hardly believe it myself - but true nonetheless! ***

Point is: how much does wall restrict these distances? If a standard OS WMR 100/200 is designed to receive over 100 m in line of sight and 50 m with a or some walls between it, can you say that the RFXCOM will do a lot better or not??

My own sensors are all within 30m of where I want to receive the data.

For me the WMR200 console was struggling with the rain gauge at 30m through 3 internal (double skin plasterboard) and one external (double skin concrete block) walls.

Factors such as RF from computers, and from Wireless networks can apparently influence matters too.

I have no technical measuring equipment but it is my firm if subjective opinion that the RFXCOM receiver is far superior in sensitivity to the OS console itself. Aside from anything else the RFXCOM has a much more sustantial antenna.

PS. Is another possibility for you to place a Meteohub within 'normal' range of the sensors, the use networking (in some sense of the word) to get data from the Meteohub to your main computers?

[J.S.]

You wrote it on this forum, in the thread "ID change, without reset or new batteries! I thought you first wrote 500 m, so I was astonished also. Thought you wrote it after the other message, in which you stated 500m (I have read this also)."
Also thoughtthat a lot of Scotsmen apparently have something with Oregon Scientific sensors nowadays...(not really) :)

Well, hetweerinbleiswijk (a site with a meteohub) has it coupled to a wireless accesspoint (well, he states so on his site and just to be sure I just asked him, am awaiting his answer). So the meteohub sends it signal wireless to the wireless router.

To answer your last question: Now, suppose I can do that and interference isn't a problem, I could place the rfxcom in a line of sight with the sensors. Well, just a wooden "wall" of a barn in between. I can place them 100-200-300 m in the country. I can choose, but the further away, the better. The country is almost flat, no trees. I want to do this to get an accurate temperature measurement. I also use a Tinytag UltraII datalogger which is very precise (max 0,1 K deviation, tested a few metres from two KNMI stations in my neigborhood, in icewater and with a feverthermometer. I want this to be in a KNMI style the radiation shield with the less precise OS sensor. The datalogger logs the real temperature, which I can read out every few months (1 hour measurements in which the min, max and current emp are stored lasts me more than a year). The OS sensor can be calibrated against the logger and will give a reasonable indication of current temperature.

Second project will be the same station placed in the warmest part of Portugal, in the Guadiana valley. This is really fun, because there are no weatherstations of the Portuguese Meteorologial Institue installed in those valleys. They are all on top of the valleys. The warmest station now is Amareleja with an average of 34,0 C as Tmax average. Also the Portugese record of 1 august 2003 with 47,4 C. The highest temperature in Europe this century btw. And finally, a record of 17 days in a row with Tmax above 40,0 C in the same year...quite impressive. But can we do better??? or worse (warmer..)
Average of 34,0 C is 1961-1990 average. Given the development in climate in nearby Spain, we can expect 35 C as a new average. In the valley it could be near 36 C. Or not....we do not know...I am very keen on getting a station working over there. In the valley, the countyr again is flat. So this station in the Netherlands will be a good test. My current station can be seen in Google by the way...also funny...

Well, a lenghty post. Hope this answers your question and thanks again for the help!

[skyewright]

You wrote it on this forum, in the thread "ID change, without reset or new batteries! I thought you first wrote 500 m, so I was astonished also.

Actually, now I come to think about it and to re-check the distance on a 1:25000 map - it really is 900m!

I guess it is so far I hardly believe it myself, and so sub-consciously 'rationalised' the figure from half a mile (900m) down to half a kilometer! :laugh:

Readings from there are however very intermittent at present. The most recent 'apearance' of those distant sensors was a couple of days ago when I got a reading from both rain & wind - maybe he was moving and servicing his equipment (the rain gauge is usually 'out of sight', the other side of his stone built cottage)?

[J.S.]

I guess you also wrote it on Weahter-watch, because I could not remember the text I just read over here (just looked it up for you in google). When I read it a few minutes ago I saw you mentioning it another time, which ruled out a slip of the pen.
SO it is 900m. May be the guy already replaced it behind the wall, as you mentioned....It is impressive, nevertheless. OTOH: I also read that the sensor in your own garden was NOT received...sigh...I'll just have to wait and see I guess...

[skyewright]

OTOH: I also read that the sensor in your own garden was NOT received

But that was before I moved the antenna to a better position (I realised that where I first put it was effectively in a 'foil' lined room due to the type of insulation in that part of the house - something called 'Airtec Double' ) and before the new firmware.

sigh...I'll just have to wait and see I guess...

That is the only test that really counts... :(

[admin]

Just as a remark:
If RFXCOM is showing sensors that belong to your neighbors' rig, you should not assign these sensors to ids. Not assigned sensors don't get logged by meteohub. That allows you to keep your neighbors' privacy in regard to sensor readings.

If you see that sensors not owned by you are low on battery, it might depend on how well your relation to your neighbors is, whether you get "don't bother with my sensors" or "thanks, couldn't we share battery cost when you also receive these signals?" :lol:

BTW, did I tell you that RFXCOM can receive the data of an rf "body mass index"-scale (BWR102). May be this is even more of a privacy concern... Don't worry, Meteohub does not decode data from this sensor B)