Model 20 GPS's stopped working this last weekend

I witnessed something pretty strange this last weekend several Cambridge Model 20 GPS stopped working. I have used it for years connected to my SN10b with zero problems. This last weekend I saw on the SN10 display, no GPS signal in the last 10 seconds over and over. Indeed it wasn't updating. I had a spare and another glider had a Model 20 that also stopped working in their glider. Has there been some type of change to the GPS signals being sent from the satellites?

This was very strange?

Buzz Graves

On Friday, May 31, 2019 at 4:50:08 PM UTC-4, BG wrote:
I witnessed something pretty strange this last weekend several Cambridge Model 20 GPS stopped working. I have used it for years connected to my SN10b with zero problems. This last weekend I saw on the SN10 display, no GPS signal in the last 10 seconds over and over. Indeed it wasn't updating. I had a spare and another glider had a Model 20 that also stopped working in their glider. Has there been some type of change to the GPS signals being sent from the satellites?

This was very strange?

Buzz Graves

Were all of these specimens of the CAI Model 20 from the same manufacturing batch, or all had a firmware update at the same time (about 20 years ago)? From what I've seen around here, a correct update makes them understand the current GPS "epoch" (cycle of 1024 weeks), as long as the internal battery doesn't die. I am not familiar with the update method but some other members of my club are.

On Friday, May 31, 2019 at 4:50:08 PM UTC-4, BG wrote:
I witnessed something pretty strange this last weekend several Cambridge Model 20 GPS stopped working. I have used it for years connected to my SN10b with zero problems. This last weekend I saw on the SN10 display, no GPS signal in the last 10 seconds over and over. Indeed it wasn't updating. I had a spare and another glider had a Model 20 that also stopped working in their glider. Has there been some type of change to the GPS signals being sent from the satellites?

This was very strange?

Buzz Graves

I expected wrong dates (from wrong GPS epoch beginning 7-April-2019),
but you still should get *something* out of the model 20.
Make sure you're running SN10 firmware version 2.45:
http://www.nadler.com/sn10/SN10_Resource_Index.html

What were the other model 20's connected to?

Anyway, its time to upgrade to a PowerFLARM and retire the '20!

Probably a residual problem from the April 6 rollover event. Not all
problems occur on the rollover date, some get kicked down the road by
firmware tricks.

I don't find it that strange, if you had a 30 year old computer that
stopped working, would that seem strange?





On 5/31/19 2:50 PM, BG wrote:
I witnessed something pretty strange this last weekend several Cambridge Model 20 GPS stopped working. I have used it for years connected to my SN10b with zero problems. This last weekend I saw on the SN10 display, no GPS signal in the last 10 seconds over and over. Indeed it wasn't updating. I had a spare and another glider had a Model 20 that also stopped working in their glider. Has there been some type of change to the GPS signals being sent from the satellites?

This was very strange?

Buzz Graves

Gary Kamerer can repair it.
http://cumulus-soaring.com/cai/GTK-C...pairs-2017.pdf

Best Regards,

Paul Remde
Cumulus Soaring, Inc.
_________________________

On Friday, May 31, 2019 at 3:50:08 PM UTC-5, BG wrote:
I witnessed something pretty strange this last weekend several Cambridge Model 20 GPS stopped working. I have used it for years connected to my SN10b with zero problems. This last weekend I saw on the SN10 display, no GPS signal in the last 10 seconds over and over. Indeed it wasn't updating. I had a spare and another glider had a Model 20 that also stopped working in their glider. Has there been some type of change to the GPS signals being sent from the satellites?

This was very strange?

Buzz Graves