Cambridge 302 and GPS-NAV owners – IMPORTANT NEWS

yep .. I waited until each had solid lock.

CLewis95 wrote:
yep .. I waited until each had solid lock.

Looms like I'm batting .500. The model 20 is fine but the volkslogger is
firmly in the 1990s :-(

Pete

Finally got a chance to pull my glider out and test the 302 today. I don't have a 303 anymore and use the 302 as my backup logger and vario so don't look at the files very often.

Using the Cambridge Utility on my iPAQ, I checked the files and there were files from July through September showing, but my last two flights in October and November were not listed at all.

I switched over to ConnectMe and it did not show all the flights back to July, but did show two flights from 1995, not a good sign.

If you are checking the files use ConnectMe to look for the miss dated files, you may not see them with the Cambridge utility program.

On Saturday, November 29, 2014 8:36:23 PM UTC-5, Tim Taylor wrote:
Finally got a chance to pull my glider out and test the 302 today. I don't have a 303 anymore and use the 302 as my backup logger and vario so don't look at the files very often.

Using the Cambridge Utility on my iPAQ, I checked the files and there were files from July through September showing, but my last two flights in October and November were not listed at all.

I switched over to ConnectMe and it did not show all the flights back to July, but did show two flights from 1995, not a good sign.

If you are checking the files use ConnectMe to look for the miss dated files, you may not see them with the Cambridge utility program.

Mine 30checks out OK for now its COJH and I don't know how old it is. What should I be doing...plug iy\t in every few weeks? send it out even if its ok?

Any way I can find out its age?

Dennis

On Sun, 30 Nov 2014 14:12:07 -0800, HGXC wrote:


Mine 30checks out OK for now its COJH and I don't know how old it is.
What should I be doing...plug iy\t in every few weeks? send it out even
if its ok?


I don't see much future in the recharge-frequently option. Once
batteries start to fail, they go downhill rapidly.

If you intend to use it long-term, I'd say go ahead and send it in.

If anyone missed the richard@craggyaero posting recently, it has lots of
good info on any logger using the Garmin GPS25 module.

FYI: I sent my 302 in last Saturday.

Gary repaired and calibrated the unit very quickly and it will most likely return ship to me by the end of the week! Wow, I'm impressed! Great service and fast turn-around at an excellent price, thank you Gary!

If you own a Cambridge 302 or GPS-NAV and, like me, would like to get a few more seasons out of it before upgrading, this is an absolute no-brainer!

Brian

The Garmin GPS-25 manual indicates the internal battery is a rechargeable Lithium with a capacity of about 180 mAh. It also says the load on the battery when the board is unpowered is 50 microamps. There is no way to see what the state of charge is on that little battery. Or how long it takes to charge it up when the board is powered. A fully charged battery is good for about 5 months. If you discharge the battery completely, the memory and real time clock will quit and you are back to 19.5 years ago again with no way to fix it other than sending it back again. So don't go too far between the new battery install and using the gps again.

My 302 went back to 1995. My GPS-NAV clock had drifted off by 3+ minutes, it did a "search the sky" when I powered it up last week and came up with the correct time.

-Dave

On Wed, 03 Dec 2014 20:08:56 -0800, Dave Leonard wrote:

The Garmin GPS-25 manual indicates the internal battery is a
rechargeable Lithium with a capacity of about 180 mAh. It also says the
load on the battery when the board is unpowered is 50 microamps. There
is no way to see what the state of charge is on that little battery. Or
how long it takes to charge it up when the board is powered. A fully
charged battery is good for about 5 months. If you discharge the battery
completely, the memory and real time clock will quit and you are back to
19.5 years ago again with no way to fix it other than sending it back
again. So don't go too far between the new battery install and using the
gps again.


Right, the manual says "up to six month charge" for that battery.
Extremely marginal for the way we commonly use the units. Since the
firmware worked correctly without battery backup for roughly the period
2005 +- 10 years, it covered up bad batteries, or good batteries that
just had been discharged. Without new firmwware to kick the can down the
road again, it's going to be on an ongoing headache.

Newer systems use a 13 bit integer instead of 10 to keep track of the
week, doubt there's any chance that would ever be retrofit into the units.

-Dave

I wonder if the affected FR manufacturers could add a mod to detect a timestamp prior to "now" and munge it to the current epoch?

Would FAI accept this solution?

-Tom

On Wednesday, December 3, 2014 10:55:08 PM UTC-8, David Kinsell wrote:
Newer systems use a 13 bit integer instead of 10 to keep track of the
week, doubt there's any chance that would ever be retrofit into the units.

On Thu, 04 Dec 2014 18:08:27 -0800, tom wrote:

I wonder if the affected FR manufacturers could add a mod to detect a
timestamp prior to "now" and munge it to the current epoch?

Interesting idea, but quite hypothetical when it comes to Cambridge.

Garrecht Avioncs seems to have source code for the GPS module, and
intends to provide a fix in that code for their Volksloggers. It should
be straightforward to add another 20 years of life that way.

As the details of the problem have come out, it's become clear that the
fix being applied to Cambridge units isn't very good and won't make them
as reliable as they were prior to November. Probably makes more sense to
just go buy a Nano or something similar if you need to replace the
logging capability.

-Dave