View Full Version : Volkslogger Date Corruption
Ian[_2_]
November 7th 14, 10:46 PM
Last Sunday my Volkslogger logged a flight but it listed the date as 19 
Mar 1995 see but the flight was flown on 2 Nov 2014. I uploaded the IGC 
to Skylines here (OLC would not accept it):
https://www.skylines.aero/flights/41031/
The "security-seal is OK" message displays on boot and the VL calculates 
a check sum before downloading. So I don't think that there is a problem 
with the battery.
I have been playing with it and I have generated a number of test logs. 
Some are dated 2005-01-01 but now it has gone back to 1995-03-24. I even 
managed to generate two logs with the same file name.
The strange thing is I got an e-mail from another club member with a 
Volkslogger, he is also experiencing date corruption with his unit. So I 
fear this is some form of Y2K bug.
Is anybody else experiencing this problem with their Volkslogger?
Any idea who might be able to fix it, if it requires updated firmware?
Any comments on how valid that log file might be? It does still have a 
valid digital signature and the points logged are correct, just the date 
header is corrupt.
I know this thing is a dinosaur and getting a log file out of it is like 
extracting hens teeth. But this is the first time I have failed to 
record a valid log file in over 12 years. I also had the barometric 
sensor calibrated at the beginning of this year so I kind of hope it has 
not just transformed into an electronic brick. :-(
Ian
Dave Springford
November 7th 14, 11:47 PM
The problem has to do with a dead internal battery in the Volkslogger.  It will have to go to an authourized center for battery replacement and so that the security seal can be reset once the unit is closed back up.
I have done this for lots of Colibri's and LX 20's, but not VL.
Dave Springford
www.foxonecorp.com
7C
November 7th 14, 11:56 PM
Strangely mine was doing that last season but has been absolutely fine this year.  I never quite got around to sending it in to get it fixed.  No idea why or how but I had been advised as Dave says it needs the battery replaced.
November 13th 14, 05:25 PM
Ian,
I had the same issue several years ago. There are two options to fix this, one is to have the GPS engine replaced, and one is to pray. I selected the prayer method (as recommended by Garrecht) and that worked for me. Replacing the GPS engine will likely cost more than the logger is worth.
The prayer or self healing method requires that you put the logger to sleep for several weeks until it looses its position completely. The older the logger is, the quicker this happens (due to the degradation of a non-replaceable battery in the GPS itself). When the logger is brought back up after several weeks or months, it will likely reconstruct the correct year.
Thomas
Craig Funston
November 13th 14, 10:50 PM
On Thursday, November 13, 2014 8:25:07 AM UTC-8,  wrote:
> Ian,
> 
> I had the same issue several years ago. There are two options to fix this, one is to have the GPS engine replaced, and one is to pray. I selected the prayer method (as recommended by Garrecht) and that worked for me. Replacing the GPS engine will likely cost more than the logger is worth.
> 
> The prayer or self healing method requires that you put the logger to sleep for several weeks until it looses its position completely. The older the logger is, the quicker this happens (due to the degradation of a non-replaceable battery in the GPS itself). When the logger is brought back up after several weeks or months, it will likely reconstruct the correct year.
> 
> Thomas
Funny! --  full circle from "prayer wheels" to "prayer loggers"
Craig
Dave Nadler
November 14th 14, 12:03 AM
On Thursday, November 13, 2014 11:25:07 AM UTC-5,  wrote:
> ... There are two options to fix this, one is to have the
> GPS engine replaced, and one is to pray.
A better option is replace the Volkslogger with a FLARM Core!
Far easier-to-use datalogger, and FLARM!
Dave Nadler
November 14th 14, 12:25 AM
On Thursday, November 13, 2014 6:19:27 PM UTC-5, Tim Newport-Peace wrote:
> Nadler > writes
> >A better option is replace the Volkslogger with a FLARM Core!
> >Far easier-to-use datalogger, and FLARM!
> 
> Depends.
> 
> FLARM is approved up to Diamonds only, but Volkslogger is approved up to 
> World Records.
Assuming anybody still cares about IGC...
November 14th 14, 09:46 AM
or world records
Ian[_2_]
November 15th 14, 10:00 AM
On 13/11/2014 18:25,  wrote:
> The prayer or self healing method requires that you put the logger to sleep for several weeks until it looses its position completely. The older the logger is, the quicker this happens (due to the degradation of a non-replaceable battery in the GPS itself). When the logger is brought back up after several weeks or months, it will likely reconstruct the correct year.
I tried the opposite of this. I plugged it in, switched off the sound 
warnings and left it on the window sill logging for a week. But VL did 
not respond favourably.
Now I will put it away and try your recipe and put it away for a while. 
Maybe one for week, then two, four, eight etc.... I just got that 
mythical battery fully charged, must I wait for it to go totally flat again?
Ian
Ian[_2_]
November 15th 14, 10:40 AM
On 14/11/2014 01:25, Dave Nadler wrote:
> On Thursday, November 13, 2014 6:19:27 PM UTC-5, Tim Newport-Peace wrote:
>> Nadler > writes
>>> A better option is replace the Volkslogger with a FLARM Core!
>>> Far easier-to-use datalogger, and FLARM!
>>
>> Depends.
>>
>> FLARM is approved up to Diamonds only, but Volkslogger is approved up to
>> World Records.
 > Assuming anybody still cares about IGC...
I do...
I am running out of badges to claim. Next will have to be 1250km diploma 
or a national record. Both are rather ambitious for me in my LS3a, so 
there is no hurry. But both would need a VL level security logger. Maybe 
I can start preparations in the meantime by praying the Volkslogger back 
to life.
In the meantime will OLC accept logs recorded by my old (non-certified) 
Swiss Flarm, or a PDA running XCSoar? I still have both of those 
options. (FYI you can upload a file with an invalid date header to 
Skylines, but not to OLC.)
What level of contest obliges the CD to insist on a digitally signed log 
file? I have not flown anything above regionals in decades. If I were to 
threaten to pitch up at a nationals could I negotiate with the CD to 
accept non-signed log files? (Please sir, I fly in Africa and I promise 
I wont trouble the top of half of the results sheet...)
What is the validity status of a digitally signed log file that just 
happens to have a date header that is exactly 1024 weeks in the past? 
Especially when it is backed by other evidence, like an identical but 
unsigned log file from another device which has the correct date header. 
This could evolve into a big appeal process for a top level pilot one 
day. Maybe I could set a precedent in the meantime.
Finally any comments. Nano vs Colibri II. Any others devices I should 
look at? (I have got a while to do my window shopping, the prayer 
process will still take many weeks.)
Ian
Martin Gregorie[_5_]
November 15th 14, 02:53 PM
On Sat, 15 Nov 2014 11:40:35 +0200, Ian wrote:
> Finally any comments. Nano vs Colibri II. Any others devices I should
> look at? (I have got a while to do my window shopping, the prayer
> process will still take many weeks.)
>
You might also consider the EW MicroRecorder - £240 + VAT + P&P.
Its a completely self-contained brick (115x85x25mm, 280g) with an 
external puck-style GPS antenna and built-in pressure sensor. It has an 
internal, user-swappable battery, takes a 12v external supply and has a 
USB connector for configuration and downloads. Both the 12v and USB 
supplies charge the battery. Uses an SD card (supplied) to store IGC 
files. It is fully IGC certified.
I have one and like it. 
Its biggest disadvantage is that the internal battery is NiMH and can't 
be disconnected: the combo of NiMH self-discharge rate and the power 
drain due to the soft power switch means that I have to remember to 
charge it every month or two during the off season. During the gliding 
season you never charge it: if you connect it to the glider's battery 
during rigging it will be fully charged by the time you derig.
HTH
-- 
martin@   | Martin Gregorie
gregorie. | Essex, UK
org       |
Dan Marotta
November 15th 14, 05:45 PM
On occasion when my CAI-302 hiccuped or I goofed in downloading it, I've 
submitted the igc file generated by XCSoar on my Dell Streak 5.  It is 
acceptable to OLC, though not for badges or higher.
As to your question about acceptance of a file during an official event 
even when backed by another file from a non-approved device, consider 
this:  You're working with a bureaucracy (contest officials).  When's 
the last time a bureaucrat bent the rules just for you?
Dan Marotta
On 11/15/2014 2:40 AM, Ian wrote:
> On 14/11/2014 01:25, Dave Nadler wrote:
>> On Thursday, November 13, 2014 6:19:27 PM UTC-5, Tim Newport-Peace 
>> wrote:
>>> Nadler > writes
>>>> A better option is replace the Volkslogger with a FLARM Core!
>>>> Far easier-to-use datalogger, and FLARM!
>>>
>>> Depends.
>>>
>>> FLARM is approved up to Diamonds only, but Volkslogger is approved 
>>> up to
>>> World Records.
>
> > Assuming anybody still cares about IGC...
>
> I do...
>
> I am running out of badges to claim. Next will have to be 1250km 
> diploma or a national record. Both are rather ambitious for me in my 
> LS3a, so there is no hurry. But both would need a VL level security 
> logger. Maybe I can start preparations in the meantime by praying the 
> Volkslogger back to life.
>
> In the meantime will OLC accept logs recorded by my old 
> (non-certified) Swiss Flarm, or a PDA running XCSoar? I still have 
> both of those options. (FYI you can upload a file with an invalid date 
> header to Skylines, but not to OLC.)
>
> What level of contest obliges the CD to insist on a digitally signed 
> log file? I have not flown anything above regionals in decades. If I 
> were to threaten to pitch up at a nationals could I negotiate with the 
> CD to accept non-signed log files? (Please sir, I fly in Africa and I 
> promise I wont trouble the top of half of the results sheet...)
>
> What is the validity status of a digitally signed log file that just 
> happens to have a date header that is exactly 1024 weeks in the past? 
> Especially when it is backed by other evidence, like an identical but 
> unsigned log file from another device which has the correct date 
> header. This could evolve into a big appeal process for a top level 
> pilot one day. Maybe I could set a precedent in the meantime.
>
> Finally any comments. Nano vs Colibri II. Any others devices I should 
> look at? (I have got a while to do my window shopping, the prayer 
> process will still take many weeks.)
>
>
> Ian
>
Ian[_2_]
November 24th 14, 10:04 PM
On 08/11/2014 01:04, Tim Newport-Peace wrote:
> The difference in dates is EXACTLY 1024 weeks.
> This would lead me to believe that possibly the RTC battery on the GPS
> Engine (nothing to do with the seal) has expired and while it will get
> the correct time, day of the week and week number in the 1024 week
> cycle, it does not know which 1024-week epoch it is in.
> This is also known to affect Colibri of a certain age.
> The solution is to replace the RTC battery and prime the RTC with the
> correct epoch.
> In practice this may mean replacing the GPS Engine, and considering the
> value of the VL, may not be economic.
In the meantime I have heard reports of another two Volksloggers and a 
Cambridge of similar vintage with this problem at our club. This is a 
high rate of failure in a small population and a short window period.
Somehow I don't think they all just happened to have this battery die at 
the same time. More likely these batteries have been dead or dying for a 
while and we have just passed some kind of Y2k date threshold which 
results in the GPS board defaulting to the wrong "epoch" on the first 
fix from a "cold start".
This implies there could be many more devices lurking with this problem 
which will come to light when the soaring season warms up in the 
northern hemisphere. If you own a logger of this vintage, I suggest you 
get it out, switch it on and check what date it logs. If your date is 
still good, make a point of powering the logger once in a while to keep 
that battery charged!
Ian
Ian[_2_]
November 24th 14, 11:13 PM
On 24/11/2014 23:33, Tim Newport-Peace wrote:
> This is probably why they are dying in droves. It is the because they
> are being unused for longer periods rather than a specific date threshold.
Mine worked on the 19th October 2014 and was corrupt 2 weeks later, on 
the 2nd November.
A 2nd Volkslogger in our club worked on the 10th October but was corrupt 
by the 7th November.
The Cambridge worked on the 11th October but was corrupt by the 22nd 
November.
(I don't have exact dates, I am just going by what my friends logged on 
OLC).
Three failures in the same windows period, all with loggers that were 
being used on a regular basis. I suspect there is more to this than we 
realize. But I will watch this space ...
If this blows up like the Blanik issue, is there scope for the IGC to 
issue special rules allowing these loggers to be used, at least for a 
year or three, until pilots have a chance to get them fixed or replaced?
Ian
Ian[_2_]
November 25th 14, 09:40 PM
On 25/11/2014 00:13, Ian wrote:
> Three failures in the same windows period, all with loggers that were
> being used on a regular basis. I suspect there is more to this than we
> realize. But I will watch this space ...
Another 7 failures reported on the "Cambridge 302 and GPS-NAV owners – 
IMPORTANT NEWS" thread:
https://groups.google.com/forum/#!topic/rec.aviation.soaring/3tHpsgoORxQ
Thats 10 and counting...
Ian
Ian[_2_]
November 30th 14, 07:52 AM
On 25/11/2014 00:13, Ian wrote:
> Three failures in the same windows period, all with loggers that were
> being used on a regular basis. I suspect there is more to this than we
> realize. But I will watch this space ...
The truth emerges. This looks like it is going to effect a lot of pilots:
https://groups.google.com/forum/#!topic/rec.aviation.soaring/0oGeJxn05B4
I will stop posting on this thread now and move further comments to 
Richard's thread, linked above.
Ian
vBulletin® v3.6.4, Copyright ©2000-2025, Jelsoft Enterprises Ltd.