OFDM Errors / Constant dropouts

RouterOS Wireless Networking
1

Hi,

For the past 48 hours one of our access points has been acting up, All the connections to it seem to constants be dropped, connected dropped etc.

We used to get 15mbps/15mbps over 24km backhaul to this radio but since this started we are struggling to get 2mbps/5mbps, we have tried changing the frequency some lower frequencies work better than others with the higher frequencies jsut dropping out as soon as you try pass any data across them.

This is the monitor of the Card/AP In question, there is another card in this unit that is a 15km backhaul which is working smooothly.

[admin@Cootha_MK1] > interface wireless monitor “SL Link”
status: running-ap
band: 5ghz
frequency: 5500MHz
noise-floor: -95dBm
overall-tx-ccq: 97%
registered-clients: 1
authenticated-clients: 1
nstreme: yes
polling: yes
csma-disabled: no
current-tx-powers: 6Mbps:25(25/25),9Mbps:25(25/25),12Mbps:25(25/25),18Mbps:25(25/25),24Mbps:25(25/25),
36Mbps:24(24/24),48Mbps:22(22/22),54Mbps:21(21/21)
current-ofdm-errors: 594 < Concern
notify-external-fdb: yes

AP:
ap.jpg
Client:
client.jpg
Bandwidth:
bw.jpg
We have had to limit the connection to 6mbps/6mbps to try keep it stable so clietns can atleast use it, we also have tried with and without nstream and had to keep nstream on due to it barley passing 1mbps without it.

Not sure what else to say, its been hot here the past 2 days mid 30’s but the other radios on the same board are working fine.

Hope you can help.

Cheers

Cameron

2

What wireless cards have you been using? We recently had a similar issue with some R5H cards

3

Hi,

The card in question is also a R5H, we will be firing up our second Unit on the same antenna tomorrow with a xr5 to try bring the link back up to speed.

Let me know what you did to resolve the issues if you have, we have upgraded to the latest OS and bootloaded etc and still the same issue.

Cheers

Cameron.

4

We changed the R5H back to R52 (normal power) and everything was fine again.

Some R5H fail if you connect them to a ‘bad’ lightening arrestor, and even some bad antennas (This is our experience anyway).

Has this happened to you?

I would suggest that if you can, use R52 and see if your link improves :slight_smile:

5

Hi,

No lightning protection just a short pigtail to the antenna. Antenna is mounted 150mtrs up a tower so its hard to get to to change we will see how our backup radio goes this afternoon.

Thanks for the info.

Cameron

6

Would be keen to hear how you get on :slight_smile:

7

Didn’t get out there last night to change to the other radio, we hope to do it tonight.

Did some testing with it last night, If I enable the second backhaul radio the RH5 instantly throws 500 - 600 OFDM errors disable it and its back to normal :S yet still unstable on most frequencies, This makes me think the R5H is stuffed.