i hav just made a wireless point to point of link 5 km , but the results are just horrible. but there is no ping timed out between them and the ping varies frm 1ms - 3 ms.
**Hardware use:
RB411+R52 + 26 dBi GRID ANTENNA ON BOTH SIDES
LINE OF SITE IS VERY VERY CLEAR( 80 FEET MAST INSTALLATION BOTH SIDES)
LOW LOSS HALF METER PIGTAIL
FREQUENCY USED = "5860 "
VERY LESS INTERFERENCE.**
**RESULTS:
POOR SIGNAL LEVEL = -91 dBm
OVERALL CCQ = 45% - 55%
SIGNAL TO NOISE = 16-20 dB
VERY LOW THROUGHPUT**
SO, anyone hav any idea where is the mistake, why i m not able to see good results at this small distance link.
Are you sure you have your grid antennas assembled correctly and the same at both ends? The feed horn in the center should be running to the the short sides. See my crude diagram below. The feed horn is in the center.
|||| | ||||| = correct
|||| - ||||| = wrong
Both antennas the same polarity? Bad antenna cable? Bad or disconnected pigtail? U.fl pigtails can pop off during assembly or rough shipping.
You should be seeing around -50dB based on your description.
hii, i would like to add one more thing.. before hooking up these units on mast.. i check them in my lab but wihout any external antenna,when i placed both mikrotik 10 mts away frm each other in my lab, singal were arround - 45 db, signal to noise was also good, and throught was good too..and imediatley after testing them i hooked them on the mast..but it shows por performance on the mast.
how can these card are damaged i never expereinced such thing. i m using these R52 for a long time. even R52 is less then 100 mw, is it not lower enough as far as power is concerend…?
i m liite surprise to accpet that these card are now damged as u said. but i always test all my mikrotik before hooking the on the mast, numerous time i hav doen it, i never got my card damaged if i checked them without any external antenna…
R52 are pretty darn sturdy. They only output about 79mw output and don’t have any warnings like the higher powered devices. I use them for most of my links.
Unless there was lightning, I have never seen a blown output on one where I have seen many blown R52H and Ubiquiti miniPCI cards.
I suspect he has bad coax, connector, or something wrong in the antenna system.
In any case, he won’t find out until he takes them down.
I have about 20 PTMP 6-10km backbone - links.
I’ve experienced a problem like yours few times , and almost always the solution was changing the pigtail.
Nowadays it’s hard to find a good pigtail.
Your Fresnel is “too good”. If your Fresnel is more than 1.0, you will have a reduction in signal strength (depending on the Fresnel). I have seen many cases where antennas were too high for a particular location, resulting in too good of a Fresnel. You may need to lower your antennas, especially with such a short link and such tall towers. I suggest using Radio Mobile to determine optimum antenna placement. It can also help you with azimuth readings for aiming antennas.
Here is an example - note the “RX Level” number, this is the predicted receive signal at the “Receiver” side.
, and I am not so keen in drawing.
