Topic: VP2 stopped transmitting. Sanity check

[zachelliottwx]

I've had my VP2 setup since July 2013. It's at a remote location about 65 miles from me, so I can't access it at the drop of a hat. It appears late last week, my station dropped off in the morning hours. Here is what almost all the graphs look like.

I checked wview and it said I had no good packets coming in. Which makes me think i've lost transmission. My soil moisture/temp sensors are still transmitting, so at least the console is getting data and I can talk to it. I replaced the battery a few months ago as well as the fan aspirated batteries since they were not holding charge. My first thought is a super cap failure since I know this is common, however, if it was super cap, wouldn't I still be getting data during the day when the ISS is powered by the solar panel? The failure happened at 7am when there were no storms or anything (checked radar) which makes me think maybe it failed the day before or so, then the battery discharged overnight? If a super cap has failed, will that cause no power to get to the ISS at all? I've read some conflicting information. I'm hoping to get my hands on the station this weekend if I can to investigate, but I was looking for some insight before I go out there regarding the power options, and if it should still be transmitting during the day on solar.

[chief-david]

I would vote supercap as the first choice.



otherwise--reset the Console...may have to take out full power, remove logger and then reinstall it.

[johnd]

My first thought is a super cap failure since I know this is common, however, if it was super cap, wouldn't I still be getting data during the day when the ISS is powered by the solar panel?

There isn't just a single failure mode for supercap-type issues. Yes, the commonest initial sign of supercap issues is loss of data overnight. But you can also get longer, maybe permanent, loss of signal. TBH given the distance and unless budget is a real issue I'd be inclined to think in terms of replacing the complete SIM board - sometimes just replacing the supercap is only a temporary fix or might not even work at all.

But, all that said, my first onsite checks would be to turn on the transmitter test LED and also to check the console channel settings just in case there's been some corruption there - probably not, but only takes minutes to check.

[zachelliottwx]

I actually have a second VP2 at my house and AFAIK it should be the same ISS board as the remote station. My plan is to go out Saturday and take a look, and take my newer board from my home station out there. If I see the supercap is blown, I can swap the boards, then take the old one home and replace the SuperCap on my own time, and the remote station will have newer equipment and back up, and my home station may be offline, but i'm the only consumer of it, but lots of people use my remote station.

[zachelliottwx]

Well I popped out to my station today and checked it out. When I got here, the transmitter definitely wasn't transmitting. I popped a new battery in it, and it started. So I pulled the battery out, and pulled it off the ISS. Once I pulled it off, I used too much force and it landed on the ground. Once i picked it up, i noticed that little green light going..... So it kept transmitting after I removed it. That's annoying. Anyway, I put the new transmitter on, and i'm gonna take the old one home and play with it to see if I can figure out why it failed in the first place. I got a new SuperCap, so we'll see if that works and i can get it working consistently at home, but my remote station appears to be all hunky dory now.

[Mattk]

Why is the little green light going? Do you have the DIP switch in test mode?

[zachelliottwx]

Yea. I set it to test mode to make sure it was working.
Once I got home, i hooked up the transmitter (with it's now dead battery) to my VP2 at home, and once I got the solar panel on, it started working and is transmitting to my console. So i'm gonna keep an eye on it but it seems to be working now, and the remote station has the newer transmitter which makes me feel better.

[zachelliottwx]

Although now that it's installed, i'm noticing a significantly less strong signal. I'm running between 10 and 40% now and before I was easily closer to 50-75. When I did the Davis diagnostic screen the graph of the signal from before and now, the new signal is lower. So i'm not sure if the new board is putting out less strong of a signal or what. I'm gonna keep an eye on it over the next 24 hours but i didn't make any console changes or anything else, except from the new transmitter.

[zachelliottwx]

So just as an update, here is what I have done. As mentioned before, I put the newer transmitter in the old station and put the old transmitter in my newer station at home. After I did this, I noticed weaker signal on the old station, like 30-40% when I used to be >70% all the time. I also noticed i still got drops. So this last weekend I bought a Weather Envoy and replaced the entire console with it. I was getting odd barometer readings when data would drop out, like it would be 30mb too high. So I decided low signal+bad readings meant a bad console. So I replaced it with an Envoy, and then noticed I was still getting a bad signal with the ISS on ID1. So I tried ID3 (my soil moisture/temp/leaf is on 2) and it still was bad. Finally I went all the way up to 8. Lo and behold, I was getting my old signal back. Very odd!
It's been absolutely solid for the past week. However I noticed tonight it completely dropped off a little after 6pm and it's been down since. However, my Soil moisture/temp/leaf sensor continues to report. This was the same issue it had before. That signal has always been solid while the ISS has had issues.
I would think interference of some sort, but it's odd that my Soil sensors have always been solid, when the ISS hasn't. Also since the signal was drastically different from ID 1 to ID 8.
I'm actually wondering if it has anything to do with the solar panel. I'm wondering if perhaps the connection from the board to the panel is lose and perhaps my battery is dead since it dropped off right after sunset. However it's been fine since Sunday when I updated it. But I did have to take the panel off to get to the DIP switches so maybe that's part of it.... I'm gonna be out there for Thanksgiving tomorrow so I can check it and see what the solar panel connection is like. Perhaps it isn't collecting as much power as it should and not keeping things charged up.

[fish-on]

I definitely would check out the solar panel. The plastic cover over the actual cell degrades over time and it can reduce the amount of energy from the sun, reaching the cells. Cells also have a lifespan and if yours are seeing hung temp swings through the year, maybe this has reduced the output of the cell. I polished a poorly performing cell once and that really helped with its output. Also do you have any tress or vegetation that has grown and possibly reduced the amount of sun that reaches cell every day. make sure the cell connection on transmitter card is tight. Connections between pins on transmitter and sockets on cell cord could be loose causing reduced energy from cell. If loose try pinching the sockets on the cell connector ever so little to tighten connection. Good luck, I think your on the right track.

[zachelliottwx]

This may have just been a fluke. It's been running steady the past 48 hours or so, and the signal has even increased ever so slightly. It came back after about 2 hours, so the solar panel definitely doesn't seem to be the fault if it came back overnight when it was pitch black. I'm gonna keep an eye on it, but this may have just been a one time thing. It's still way more reliable than it was before I changed the transmitter ID and replaced the Console with an Envoy

[fish-on]

glad it`s working. One thing with electronics that operate outdoors is that overtime, the pollutants and moisture in the air can get on connections and cause resistance issues on low current flow connections. The electronics board looks like it has some sort of conformal coating to protect traces and solder joint. The battery, solar panel and sensors connections do not. Those connection can have issues with contamination from the air over time. When I do my yearly cleaning I make sure I inspect all the open air connections for corrosion, pits, rust, etc. Flakey looking connections get dressed up to make sure they will transfer electrons properly. Maybe all the making and breaking of connections cleaned things up and gave you better continuity on the connectors and battery clips. 

[zachelliottwx]

So far so good. I've had a few drop outs but they are usually a minute or two and it recovers quite handedly. Here's the graph for this week so far (so 3 or 4 days) and it's been pretty consistent. (I'm using Zabbix to track everything)