ePMP 1000 GPS (lite) AP just lost all GPS

We are in Canada, the puck orientation has made a fairly large change in the number of tracked and the quality of the recieved signal on the GPS. On pole mounted AP's we use an exhaust U-bolt clamp and a small steel plate to hold the puck antenna so the cable is verticle and out the bottom (towards earth). We also found that the use of electrical tape is prefered over zip-tyes or wrapping the cable around the pole. Excess cable should not be looped as this causes issues with the gps signal. We found running the cable out and making a second pass on the pole with the cable works well as long as the cable doesnt loop.

Just my $0.02 but that has basically solved the gps issue for us aside from the fact that most of our sites use the Packetflux Syncbox and the gigabit injector, which is the way we are planning to continue to sync our sites and keep the onboard gps as a backup.

It would be nice if the ePMP guys could do AutoSync like Canopy. Prefer CMM3/4 and fail over to on-board GPS. I suppose FreeRun aka internal/generate wouldn't be a bad option to have either.


@George Skorup wrote:

It would be nice if the ePMP guys could do AutoSync like Canopy. Prefer CMM3/4 and fail over to on-board GPS. I suppose FreeRun aka internal/generate wouldn't be a bad option to have either.


Yes, that would be very nice. They do kind of have free run already, with the Synchronization holdoff time setting... it just can't run for more than 24 hours that way.

I think there is more to this GPS issue...  I just installed a second brand new 1000 AP with the new GLONAS puck. It has the same problem as my previously new install.

This 1000 AP with GLONASS puck is sitting right next to two 2000 APs with the same puck. The pucks are all within 1 foot of each other with the same orientation.  Both 2000 APs are tracking 14 satellites. The 1000 AP with the same new puck is tracking 6 satelites.

My other 1000 AP with the new puck is also tracking 6 satellites, all with SNR below 30. It drops to 0 satellites tracked through out the day. No change to the 2000 APs.

My older 1000 APs with the older pucks have 12 - 15 tracked satellites and most have SNRs in the 40's and 50's.

I think the new GLONAS pucks do not work well with the 1000 APs.  I now have two 1000 APs with new pucks acting exactly the same (poor SNR, low tracked sats and dropouts to 0 satellites on a clear day).  I have 4 1000 APs with old pucks that work perfectly and two 2000 APs with new pucks that work perfectly.

This is more than puck orientation.

2000 AP with GLONAS puck:

1000 AP with GLONAS puck 6" away from the above 2000 AP puck:

Hate to keep revisiting this topic but the problem continues and I can't run SYNC on one of my 1000 APs.

This AP is at the top of our tower. It is next to two 2000 APs - all clustered at the top. The GPS pucks are mounted with clear view of the sky and are all 2' from each other.

Three days ago at 5:34am, the 1000 AP lost all satellites and stayed at 0 satellites until I changed it to flexible mode (where it still is).  Thinking I am having an issue with the new style pucks, I climbed the tower and replace the GPS puck with the old (non-GLONASS) version. I verified the GPS cable was clear with no tight loops and the puck has a totally un-obstructed view of the sky.

Changing the puck had no effect at all on the satellites. It still has 8 visible and 0 tracked. Of the 8 it can see, SNR is all below 10.

If I check the two 2000 APs right next to this 1000, they all track 14+ satellites with great SNR.

So, this tells me it is not hardware with the puck and it is not reception / interference.  There are no cell carriers on the tower (in fact there is no cell service up there). We do have some low power FM stations and a low power UHF TV station on the tower but all antennas are more than 10' away from the APs and GPS pucks.

I had no issues up until 5:34am the other day - its been up there for months.  The only thing new on the AP is the fact it has been running 3.3rc-14 for 14 days. 

I bet if I reboot the AP, GPS will come back. However, without knowing what is killing it, I don't want to start this battle.  

Bad AP?

Hello,

Since this AP is running GPS firmware AXN_3.20_8174, it means it is using the updated GPS chip (same as ePMP2000), which can track both GPS and GLONASS satellites. So this AP will benefit from using the newer Taoglas (squared-ish) GPS antenna.

Since you have used both GPS antennas and nearby APs are not having GPS tracking issues, and you continue to see this issue, I would recommend submitting a ticket with our Customer Support team and make sure to include all the troubleshooting you've done already (probably want to include a link to this thread). If the AP is under warranty, they should be able to help you with the RMA process.

Regards