[danner]

I am quite frustrated at this point and don't know what else to do.

Don't know if there is any connection but we had a few days of unseasonably warm weather and now my TX0 board, which is what the temperature sensor is connected to, is not sending the temperature. I don't know if it is the sensor, the transmitter, or something else?

I am getting -- displayed for the outside temperature. I first noticed -- on my wireless display so I went to the receiver and it also had -- for the outside temp. I looked at the RF from the transmitters using my RTL dongle and it appeared the TX0 frequency had drifted on top of TX1, unfortunately TX1 is only 15ft away while TX0 is at least 100ft away.

Anyway, I swapped out the transmit module and it is still occasionally displaying -- for the outside temp.

How do I test what is wrong without changing every single component?

The voltage is above 12.95VDC when it happens so don't think it is a voltage problem? Nothing else has changed.

This is what the RF waveform looks like on TX1, TX0, and the relay. For whatever reason TX0 no longer comes to a nice peak like TX1 or the relay. I don't know why they look different as they are supposed to all be the same thing, but they were sourced from different vendors. As you can see TX0 has two peaks and I don't know why that is, whether it makes a difference, or if that is what is causing the problem?

[werk_ag]

My best suggestion is don't start changing any components, instead, try to adjust the position of receiver and /or TX0 transmitter antennas. Sometimes having them in horizontal position (just one or both) works better than having them in vertical position (thats what happen with me). Do some experiments, leaving the TX1 as it is.

[danner]

The positions of antennas and arrangements of anything inside the house near the receiver, or in the back yard between the receiver and TX0, has not changed. Some part had to have failed.

It makes no sense why a system would work practically flawlessly for months to suddenly stop working? There are no other 433.92MHZ devices of any significant strength being received so I can't see what is happening being caused by another transmitter nearby.

TX1 is on the roof about 15ft directly above the receiver. Absolutely no issue with TX1 or the sensors connected to it.

TX0 is the original transmit board I've had and have been using since I first started this. It is in the back yard about 100ft or so away.

I just measured the battery voltage with my multimeter and it is 13.01VDC fluctuating to 13.00VDC on transmit. 13.00VDC at the terminals on TX0.

[werk_ag]

Dan, I'm just trying to help. Believe me, no part has failed. What I'm trying to say, is for you to try to give some privilege on reception from the TX0 unit. Its hard for me to explain technically, but when the frequency of a TX module drifts (and they drift with temperature) from the frequency of another TX unit with a stronger signal, the RX module tends to not receive the weaker signal.
Try playing with the position of the RX and TX0 antennas, until you get a good reception from both TX0 and TX1

[danner]

Yes, thank you. Appreciate the advice.

That's exactly why I swapped the transmitter module because it was right on top of each other.

I installed a header this time instead of soldering it directly to the board. I changed out the TX module again and now it seems to be receiving TX0 reliably again, but it has only been an hour or two so I don't want to say it is fixed yet. Hopefully this module doesn't drift that far down in frequency.

Lost almost an entire days worth of temperature data. Very frustrating.

[danner]

I wonder about possibly getting a small heater for the crystal to maintain a specific temperature to minimize drift, also known as a crystal oven.

[danner]

So far so good since swapping out the transmit module the 2nd time to get it a little further away from TX1's frequency. Time will tell though!

[danner]

TX0 still going with the new transmitter module. Looks ok.

I'm going to do my best today to install the inspeed wind gauges. Was supposed to install them previously but the issues I had with TX0 took up that time. Happy it's working though.