MaxiSpy

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Weather and Pollution
I'd like to add a little on something Eddie said. He does hit one nail on the head in saying the "toy radios were designed for room temp", but I think there's more... I think that it's important to remember that when we stretch this stuff out over distances - many factors are pushing the hardware & WiFi drivers/software in these "toy radios" well beyond their original design intentions.

Now, does that mean WiFi is not well suited for what all of us are doing? No! In fact, in spite of the original design intentions, it works pretty good... well, most of the time.

We had rain yesterday almost all day long. During the afternoon, a thunderstorm blew in and for no reason, one of my nodes began using a different pathway (marginal route) to reach the gateway. The odd thing is that the segment looks like this:

NODE A  ---   GATEWAY   ---   NODE B (The gateway is about halfway between node A to node B, and all 3 are in the same line with each other. Node A just quit meshing with the gateway and jumped clear past it to Node B to repeat back into the gateway.

However, looking at maxispy (enhanced version of sigspy) from Node A, the signal of the GW node was down in the noise. In fact, almost everything was! The gateway could not hear Node A very well either. I was going to swap out radios after church today, as my thoughts were that static from the thunderstorm may have toasted the radio. However, I just got in from church and looked at it and the SNR values are all back where they should be!

It's important to say that there was a power failure in that part of town during the storm and when it came back on, this route changed. I'm thinking there is a lot more that affects this stuff than I once believed. These radios are just short-range products we've stretched with antennas. I think temp changes, static, and even local noise takes more of a toll than we think sometimes. I wonder if an electrical transformer may have began generating more noise after the power came back on? Whatever was the case, it has quit and the optimized route is now being used again.

That makes me wonder if there is something else in your environment causing this? Could static be the culprit? Or, was there a sudden change in temp or humidity right before your problems? Like I said, I think there is a lot in the environment that affects our RF.

The good part is that with mesh, we are well suited to deal with most of it.

if > the temperature was between 0 -40 C that I would be ok however seeing > the temperature increase on the motherboard then would really concern > me. We have people near the equator having similar systems in place I > would be interested how they cope? >> this is not something i know for a fact but its just something i >> believe.. i think the actual operating equipment temperature plays >> a big role.. all solid state devices generate more and more noise >> internally the hotter they get.. at the same time the analog >> amplifier circuits on the recieve side and on the transmit side can >> also change enough to actually make the devices move out of the >> analog section of their origional linear bias curves causing even >> more noise and just one fact in this hypothesis the effiency of all >> the amplifier circuits degrade as u move above room temperature.. >> gawd now ya got something to really think about hahahaha  have you >> tried an ice pack on your nodes??? seriously these little toy radios >> were designed for room temperature and most of us have them deployed >> at far greater temperatures..

>>> I normally would put this on my Blog but in this case I am having a >>> problem with the weather. In Toronto we have four distinct season >>> and we are in late spring right now. The leaves are on the trees >>> and we have normally breezy days. Lately we have still days and the >>> air pollution has increased. I keep loosing a number of nodes. >>> They have to physically rebooted. Then they loose connectivity >>> again and then I have to reboot. When the temperature is cooler the >>> connectivity improves. When it rains, believe or not, everything >>> works - just the opposite of what you think. >>> I just wondering if anyone else experience the same thing?