XR9 Cards dieing, why?

Hello,

I have a lot of small wireless networks running 900MHz using XR9 cards, we were using SR9 but have recently been forced to change due to lack of supply.

We have about 120 small networks each with 10 or so clients, one AP-Bridge and the rest station-WDS. This has been working for us with the SR9 cards for quite some time now. Now that we have moved to XR9 though we are noticing a lot of these cards that are not working very well and I’m not too sure why, is anybody else having trouble with these or is it something we are doing? I have noticed the signals are way better using XR9 so maybe they are running a bit hot on the TX power?

the one I’m looking at currently has the following stats:

Signal Strength: -65dBm (normal)
tx-signal-strength: -68dBm (normal)
noise-floor: -98dBm (normal)
signal to noise: 33dB (normal)
tx-ccq: 16% (low, normally 70-100%)
rc-ccq: 34% (low, normally 70-100%)
p-throughput: 952 (low, normally 4500 or so)
overall-tx-ccq: 16% (low, normally 70-100%)

Replacing the XR9 normally seems to fix the issue, but it seems like its happening more and more, replacing them right and left…
If theres anything anybody can tell me about this that would be great, I’m beating my head against a wall here

what types of antennas are you using, are they DC Grounded?

We are using these: http://store.wisp-router.com/catalog/partdetail.aspx?PartNo=MA9-5N
so no, they are not DC Grounded.

Iv actually never come across DC Grounded antennas before, is this a common practice? Does not having them cause trouble?

Google, here I come!

If the antennas you are using are not DC grounded, they can pass any type of current directly to the radio. Whether it be lightning or static electricity.. there are several posts about this, let me see if i can find one real quick for you.

How to check antennas:

http://wiki.mikrotik.com/wiki/Wireless_card_diagnostics

Info on DC Ground Antennas, and why they blow cards RF ports:

http://forum.mikrotik.com/t/wifi-cards-keep-blowing/33759/1

http://forum.mikrotik.com/viewtopic.php?f=7&t=9734&hilit=pacific+wireless+omni&start=0


This may, or may not be the source of your problem. But it is likely.

-Brad