Is this 900Mhz PMP100 AP bad ?

After storms we had to replace several 900Mhz PMP100 APs this weekend and as it was done in a hurry the radios were configured but not updated at first.  So at first the APs firmware was 13.1.something  while all the other APs in the area and customer radios were 13.4.1  and at that time all the replaced radios exhibited the problem I am posting here about. However we had seen this before when not all APs had the same version of firmware.  When we updated the APs to 13.4.1  the problem went away on all the APs except one.   

In the pics I attached you see most of the radios show with only a LUID/MAC and it says they are "Out of Session" however they are in fact in session, we can access the radios via their management IP and though the AP shows hundreds of session counts  the radios are not actually dropping connection.  In fact we would not have known there was a problem other than the fact that the affected radios will not initiate a PPPoE connection so the customer has no Internet. Even rebooting the customer radio or AP the customer radio will not attempt to make a PPPoE connection. But if we log into the radio and manually press the "Connect" button on the PPPoE Tab then PPPoE connects and the customer has internet until the radio reboots or drops the connection or whatever.

All APs are v13.4.1  and all customer radios (with only a couple of exceptions) are v13.4.1 .
This problem did not appear until we replaced an AP.

As you can see in the Pic there 5 radios that work as expected.
The lwaters.220 radio works while the radio 2 above it on the list is a few hundred feet away , has the same signal strength, same firmware, same everything but lwaters works and the neighbor's radio one of the radios showing as not connected/dropping etc..

You can also see leon4tgh.211 on there, look at that crap signal strength, if anyone was going to have problems I would expect it to be that one but it's chugging right along working fine (we are very rural and have a very low noise floor but this radio is pushing the limits even for our area).

There appears to be no rhyme or reason to why those 5 radios work while the rest do not.

Any ideas ? Is our new AP faulty ?  

Edit: forgot to mention I have double checked all the AP settings to make sure ALL the AP's are receiving GPS sync and all are set to the correct distance/ratio/control slots and all are using the same channels they were using originally.

It is hard to tell whether the hardware has an issue in this case or not... based on what you've presented it sounds like the noise floor, interference level or lack of SNR is simply preventing solid connections for several of those SMs.

Do you have a spectrum scan at the AP or at any of the locations where you're having trouble?  This may tell you what noise the radios are actually seeing, and may suggest you make a frequency change if that's possible.


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The problem here is that since the SA on these radios is not GPS aware the only thing it is going to see , and it will see a lot of it , is every single otherPMP100  900Mhz we have for 30+miles in every direction (not to meniton the other 3 pmp100 900Mhz APs on the tower right next to it).  So before I'm willing to shut down my entire 900Mhz network just to SA this one AP I'm going to need some kind of compelling evidence that the problem is in fact noise.

To me, this  doesn't seem likely to be noise  when, as explained in my previous post, -

(1) I have someone working just fine a -88  and someone at -57 that doesn't  work  (both are directly north of the sector, the sector points directly north  the -88 is abouot a mile beyond the -57 on the same highwy, so almost directly in line with the -88)  

To me if there was any noise of any kind that -88 would not be there or it would be one of the radios having trouble... it would be the one having the most trouble.

(2) The -57 that is not showing up correctly on the AP is 400 feet behind,  and directly in line with, their neighbor who is also at -57 and the neighbor shows up correctly and works correctly  it's also a mile in in front of and directly in line with the -88 customer that works just fine.

(3) The radios that do not work, consistently don't work and the ones that do work consistently work. 

(4) These all worked right up until we changed the the AP, the previous AP did not have this problem.

Additionally the radios that are not showing up correctly and won't start a PPPoE connection work just fine after you manually connect the PPPoE and when I run the link test at the full 10 seconds most of them get  98-100% up/down.

All of our radios are on 906 and 924  this AP was originally on 906 but we tried 924 and 915 (currently it's on 915 simply because we don't use that channel normally) with absolutely no change in the problem right down to the exactly same radios working and the exact same radios not working.

So if, just for the sake of argument, we assume that noise is not the problem (because I'll climb the tower before I'll shut down my entire network to run a SA on a single AP)  then does that mean the radio hardware is likely faulty ? 

Went up tower, replaced the radio in queston, problem solved.  

Still don't know if this radio is physically defective or if we could possibly default it and reload firmware or something or if we should RMA it or what.

Glad the new one is working for you.  We retired the PMP 100 series products January of 2016.  If it's still under warranty, we will support you if it's a hardware defect of course, but there is also likely a large supply of used (and very affordable) PMP 100 equipment available through third parties...

In addition, I would like to recommend trying our updated PMP 450i version of the 900 MHz product.  You can eek out substantially more capacity from this spectrum using the 450.  There are many folks on the forum that can share their stories of the migration from PMP 100 to 450 in the 900 MHz band with great success.

Here are a few:  





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