X9D+ No Longer Logging Telemetry

[J_B_Wingnut]

I went to check the telemetry log after a recent flight, and discovered that my transmitter has not been recording logs for the past couple of weeks (probably a couple dozen flights on three or four airplanes). Logging had been working perfectly for a couple of years until suddenly it didn't. I've spent a lot of time over the past few days trying to get it to start recording logs again, with no luck. I've provided the details of the situation below. I've tried everything I can think of to get logging working again, and have run out of ideas. It's probably something simple stupid that I've just overlooked. Any suggestions on what to try next would be appreciated...

Indications:
1. The only thing that changed since the logging ceased is that I did some minor programming changes on ONE of my models. I added a "suedo-lap counter" display for pylon racing, that uses global variables to count and display full-elevator pulls. I have not touched programming on any of my other models in months.
2. I currently have no logging on ANY of my models. I use 8XR, 6SR, 4XR, S6R, and S8R receivers on the various airplanes.
3. Logging is enabled via Special Functions and Logical Switches: Logging is supposed to begin when the motor is armed using Switch F aft.
4. The transmitter receives and displays real-time telemetry data.
5. The "SD card writing" indicator/icon is displayed on the transmitter screen when the logging should be occurring.
6. All other functions appear to work correctly on all my models/airplanes, including throttle arming, flight controls, rates, expo, etc.
7. I have never opened the case of the transmitter in the two years I have had it, and it has never been dropped or abused. I replaced the battery three or four months ago. I keep the transmitter in a Taranis soft case.

Things I've Tried That Didn't Resolve The Problem:
1. I made sure all my Sensors listed on the Companion Telemetry page were checked (for all my models)
2. I re-checked the throttle arming and logging logic in Logical Switches and Special Functions, and confirmed operation in the Companion simulator using the Logical Switches, Special Functions, and Global Variables windows.
3. I went through each of my airplanes, running them, to make sure they all functioned properly, and to confirm they all have the logging problem.
4. I changed my logging logic to a simple on/off switch independent of throttle arming.
5. I checked the SD card slot for dust and foreign objects, and proper operation of the spring-loaded card insert/removal mechanism.
6. I checked the capacity of my SD card (1GB card that has only used 300Mb)
7. I inserted the SD card into my computer to ensure all the files are really there, and can be accessed.
8. I transferred all the SD files onto a new SD card, and put the new card into the transmitter.
9. I reverted to a two-month-old EEPROM file backup of all my models (I know for sure everything was working back then)
10. I updated the firmware to version 2.2.2 (I had been running 2.2.1)

 

[J_B_Wingnut]

In case anyone having this problem comes across this post, be advised that the problem is solved! Someone on another forum responded to my post, saying he had had the same problem, and had gone through the same steps as me without resolving the problem, and had finally found the solution: Replace the RTC battery! That's what I did, and now all is good.

In case anyone else has this problem and comes across this post: The RTC battery size is LR 1220, 3V Lithium. The measured voltage of the old battery I removed was 3.04V. The measured voltage of the new battery I put in is 3.32V. If someone has this problem and measures the voltage of their battery, be advised that 3 volts on a 3 volt battery is not enough! Also, my transmitter is 2 years old... so that's how long my RTC battery lasted. Anyone with a transmitter that old should have an extra RTC battery in their flight box

 

[Konrad]

Thanks.

RTC? =Real Time Clock?
Wayne has no issue with cross posting to other sites. So if you have a link it might be helpful for others.

 

[J_B_Wingnut]

Yes, RTC = Real Time Clock. Answer came from OpenRC Forums:
https://openrcforums.com/forum/viewtopic.php?f=97&t=11389&p=139874#p139874

 

[Wayne]

Interesting. I would not have thought of the battery being an issue. Thanks for the feedback!!

 

[J_B_Wingnut]

Kinda makes sense, I guess, after thinking about it a bit. When the transmitter creates a log, it appends the transmitter time and date to the filename. If the battery isn't powering the internal clock, then maybe the transmitter doesn't know the time and date, and thus cannot create the file. That said, I'm reserving judgement on the fix pending some additional testing. I went to the field yesterday, and had some other weird things going on. One plane flew without any hitch, but on another, only the throttle would work. Also, the transmitter clock had reset to Dec 31 1999. Gotta do some more investigation. Could be the battery/logging issue is just a symptom of a deeper problem.

 

[Konrad]

I love this kind of feadback. It is always good to learn new things. Even if with luck, I don't need to use this knowledge.

Your Dec 32 1999 issue is with the radio that only the throttle would work? This "working throttle" was for logging throttle telemetry only or was this the only output you were getting from the TX?

All the best,
Konrad

 

[J_B_Wingnut]

So my bad on my previous post. Turns out that I am the "deeper problem". The airplane controls issue was due to human stupidity. I neglected to cycle the sticks when I did a receiver stabilizer check on the S6R receiver. I did another check procedure, this time the correct way, and all controls now function normally.

I took the transmitter case apart and checked the RTC battery placement. Maybe, just maybe, the new battery wasn't completely seated under the little retainer strap on the left side of the battery holder, and could have had a momentary break in the battery contact. I removed the battery, bent the little contacts out a tiny bit, and replaced the battery making sure it was properly seated. I reset the time and date, and now everything seems back to normal. I'll report back if the problem resurfaces later.