Temperature data spikes revisited

[Gina]

Disconnecting the anemometer didn't stop the spikes so I've now reconnected the anemometer and disconnected the wind vane circuit. As of 11:30 today.

Here's the latest plot :-

6hrs-Temp-only6.png

[Gina]

Still getting spikes so I've now (as of 13:30) disconnected both wind sensors. If there are still spikes, something has changed and a completely new rethink will be required. eg. could it be the cable to the rain gauge (still connected).

6hrs-Temp-only7.png

[Gina]

Still spikes!!! So I've unplugged the rain gauge as well.

[mcrossley]

or it is RF interference?

[Gina]

AND STILL THERE ARE SPIKES!!! I give up (well, for the moment). I'm going to reconnect all 3 sensors and leave it for a while.
Edit... all re-connected as of 15:15.

If anyone has any ideas I'm "all ears".

Here's the latest plot. The little hump at around 14:20 is where I held the transmitter to unplug the rain gauge.

6hrs-Temp-only8.png

[Gina]

or it is RF interference?

I don't know any more! But, guess what, since I re-connected everything it's dreadful (like the weather) - what have I done? I don't know. Anyway I've had enough for today and it's starting to get dark now and raining again, as well as cold and very windy (just hoping my mast will stay up!).

6hrs-Temp-only9.png

I think tomorrow (if the weather lets me) I'll bring the transmitter unit indoors - the cable from the wind sensors will just reach. And extend the rain gauge cable. Though if it's fine there's no need to connect the rain gauge. I have a small hand-held digital oscilloscope so I'll see if that shows anything.

[nking]

Mine went crazy after I extended the wind cable, after I removed batteries from both transmitter and Logger to reset them both it sorted itself out, you might want to try that as you have been swapping cables around.

[Gina]

Mine went crazy after I extended the wind cable, after I removed batteries from both transmitter and Logger to reset them both it sorted itself out, you might want to try that as you have been swapping cables around.

Worth a try, thanks

[Super-T]

MI6 haven't got a secret transmission tower nearby have they?
Following all your testing it would appear to be RF interference. How about move it to a relatives house a short distance away and try it there?
How many times have you been round and round in a circle now?

[Gina]

MI6 haven't got a secret transmission tower nearby have they?

Not that I know.

Following all your testing it would appear to be RF interference.

I still think it is, yes.[/quote]

How about move it to a relatives house a short distance away and try it there?

No relatives anywhere near but I do have friends. A possibility though not very practical, I'm afraid.

How many times have you been round and round in a circle now?

Gawd knows! Far too many, that's for sure. But I'm determined to nail this one! Probably be engraved on my tombstone

Testing continues...

About 08:10 I unplugged the RJ11 connector from the transmitter unit, disconnected the earth and brought the cable from the wind sensors plus circuit board and 2" cable to RJ11 plug, indoors. Everything to the left of the dashed line in the diagram below. Then at 09:30 I unplugged the rain gauge and brought the transmitter unit indoors. Next will be to plug in the circuit board with wind sensors.

AWS_Link_Circuit2.png

The results up to 09:45 are below.

6hrs-Temp-only-a.png

This shows that with NOTHING plugged into the wind RJ11 socket on the transmitter there are no spikes! The rise in temperature when I brought it indoors can be seen, as expected.

Can 2" of unscreened cable from cct board to tx really pick up tons of interference?! The results with the cct board disconnected and RJ11 connected would tend to indicate so. But I don't believe it! Going to try another RJ11cable plugged in.

Edit... RJ11 to BT, 4 wire cable plugged in to Wind socket on Tx unit at 10:15.

[Gina]

OK Next results... RJ11 to BT cable - no spikes. Reconnected wind stuff (no filtering - direct linking) but without screen earthed - spikes galore!

6hrs-Temp-only-b.png

Later... Screen connected to mains earth - no improvement.

[Gina]

Unplugged the circuit board as shown below and this time, it's stopped all but one small spike.

6hrs-Temp-only-c.png

AWS_Wind_Connectors.png

[Gina]

From 14:15... Anemometer only connected - just a few spikes.

6hrs-Temp-only-e.png

AWS_Anemometer.png

With the scope connected to the RH anemometer connection I get a nice rectangular wave of 3v amplitude (0-3v) as expected. The scope ground was connected to battery negative.

Now I'm going to plug in the full connection cct and see what the wind vane connections show.

Results... the RH connection shows an intermediate voltage with occasional large pulses. These may well be causing the temperature spikes. BUT the LH connection is showing 3v rectangular waves like the anemometer connection next to it. So I suspect a short between the two. I'll disconnect from the transmitter RJ11 and check that now.

Results... The short mentioned above was my fault A fine solder bridge between two of the 0.1" strips on the board left behind when I unsoldered the capacitor last time. Now both the vane connections show 3v. The anemometer shows 0v and the rectangular wave as the reed switch opens and closes as the cups rotate. That short was the cause of the mess on the temperature plot!

[hans]

since you have your outdoor unit in the house now,why not check the pcb.
make sure there is no dirt ,corrosion etc.
bad/loose soldering(resolder when in doubt),go with a small knife or something to clear any possible shortcut between the tracks and

or is it just jinxed??

[jim-easterbrook]

Now both the vane connections show 3v. The anemometer shows 0v and the rectangular wave as the reed switch opens and closes as the cups rotate. That short was the cause of the mess on the temperature plot!

Which confirms that interference on the wind vane wires can affect the temperature plot.

I'm wondering if the anemometer square wave could be causing interference in the wind vane circuit. If none of the reed switches is closed this would be a high impedance circuit that might pick up interference quite easily. I think you've mentioned that some of your reed switches don't close Gina? It might also explain why some (or most?) of us don't have a spike problem.