R52 as b/g AP loosing power/sensitivity

Hello

We have a number of R52 sitting on RB532 boards, running as AP (2.9.27). On a few of these, we have seen significantly loss of power and sensitivity after some weeks in good operation. The problem comes gradually, and the signal loss is at least 10 dB.

It looks like bad pigtail/cable/antenna, but when we replace the card, everything goes back to normal.

Does anybody have an explanation ???

Static Discharge slowly kill your card.

Thx
//Budi

Budi, pls be more specific.

With static discharge, you probably think of one of these cases:

a) static discharge, while I’m handling the card: I’m handling a lot of cards and routers. Why is it only R52 on a few of them that can’t stand my treatment ?

b) thunderstorm: We haven’t had any this summer yet…

c) static energy generated from wind friction on the antenna etc - combined with the lack of proper grounding: If this is the case (and it could very well be), then why is the other card (a CM9) in the router for 5 GHz uplink not dying ???

Hi,

we experience the same with AR5001X-Cards in our Proxim
Tsunamis. This seems to be site dependent. At the moment
we are asuming it depends on operating temperature as the
sites with the highest temperature have the biggest problems.

Maybe cm9 are more robust than the other cards ???

Stefan

Hmm, different grounding treatment ?
Different antenna, one dc-grounded, and one not dc grounded (that connected to dying card) ?

You would be better monitoring the situation, if other card
dieing in same antenna, better check :

  • Your grounding situation for that antenna
  • Are your antenna dc-grounded by design or not (ask the manufacturer) ?

Thx
//Budi

We are having exactly the same issues here, we have previously been installing and supplying CM9 and WLM54AG’s, we recently purchased a batch of 100 RB52’s out of which 10 are giving us exactly the same symptoms as you have pointed out, works for a week or so and then signal strength drops by 10-20db. One thing to note is that in most cases these cards are either been used in conjunction with CM9’s in the same board or we have replaced a CM9 on a site that has been working perfectly for months to test the RB52 and the problem then arises ONLY on the RB52, replace the card with a CM9 and problem solved.

We have contaced Mikrotik who seem to be unaware of any issues :open_mouth:

We are experienced installers handling on average 50 installs a month with a combination of CM9, WLM54AG and RB52 and ONLY RB52 is giving us problems.

Also another thing to note is that geographically the problematic installs are not confined to a specific region we have reports from regions that are some 2000km apart so I cant see it being related to local weather.

I have just placed an order for another 200 units which makes me wonder if I should perhaps rather stick to the reliable CM9 until the stability of the RB52 has been confirmed.

I’ve blown a bucket load of cm9’s
worst is on omni’s, not really problem on backhauls

I;m going to run a small bit of copper wire up the omni and into the ground, see if that helps.

I find also this is very site dependent.