Hi.I am having a very strange problem with a link for 10 days now.It fails during night
and restores again after sunrise.I am using a rb433ah(os 3.20)+r52 and pac
wireless 5ghz-19dbi panel at one side,and a rb411a(os 3.28)+cm9 with wavearena
30dbi grid.The distance is 1.200m and both cards are tx fixed to 13dbm.
I have already changed the feedhorn to the grid,changing frequencies and
leaving the tx power to default but no change.The area is clean from other radios
that might causing interference.During daytime i have -65dbm 24db snr and it drops
down to -90dbm 8db snr at night.I also have pure los between the links and it was working
perfect for 20 days after installation.
Can anyone tell me what could possibly cause this failure?
sorry for not being accurate the distance is 1200 meters.
the signal i get with 13dbm tx power is -65dbm and stable during daytime.i suspect that
the 19db panel with 12 degrees beam width (vertical polarity)
is responsible for not having better signal.Nevertheless the problem
is during night hours when it drops up to 25-30 dbm.
Over much longer distances I can achieve those signals from a 19db panel to a 5db omni.
Something else is wrong.
Is it truely a clear line of sight?
At what heights are your antennas mounted?
The reason I ask, is that the freznel does have to be taken into account.
What kind of environment, country side or urban jungle with many highrises?
You need to describe in much more detail the link conditions and environment.
the panel antenna is at 70 meters from sl and mounted to 1,60m from the buildings roof
the grid is 110meters from sl and the mast height is 3,20 meters.both sides
clear los and the freznel zone is not having any obstacles like power lines or radars,
metal constructions or whatsoever.I have also noticed that the signal failure starts
usualy 30 minutes before sunset and it lasts for 6 to 8 hours and then it restores back to
normal.The area is countryside and after doing exccesive scans there are no other 5ghz links present.
Have you tryed a re-aim after or around sunset?
If you can be aimed to remain up at night, and it drops during the day, then there is surely something affecting the microwave field.
Well it must be interference or whatsoever.Yesterday i set the cards tx power to default(19dbm max) and the link had a small
drop of 5dbm insted of 25dbm whitch was in 13dbm fixed power.The most important is that it stayed locked in 54mbps and the tx\rx ccq was 100%.
The reason i reduce the power is for keeping the noise and the spectrum clear and of course that 19dbm are way to much for a 1 mile
link.Something must jamming the signal.There is no other rational explanation to this one.I guess i will have to leave the cards to default.
(58dbm signal).
Sounds like it could also be water ingree into your cable/connectors.
At night it will condensate due to the colder weather and form into droplets shorting your feeder cable out, when the sun comes up it will heat up and vapourise and your feeder cable is once again un-shorted..