I have 2pcs of groove 52hpn which I got for simple ptp link. Problem is at the site1 where SNR from site2 is pulsing (20-35dB). Site2 is receiving site1 with out any problem SNR 38-40dB. I tired everything, swapping groove's, swapping antennas from site1 to site2, no change.

Antennas are 2pcs of Hyperlink grid 2.4GHz 24dbi. Before I got groove's I used 2pcs of WL-5460ap V2 for 10 years with out problems. Because those APs are very old I decided to change them with grooves. I must say that I have NO line of sight! But that should not be a problem as with WL-5460ap link worked. I had file transfer 2Mbyte/s - 3Mbyte/s (usual 2.5Mbyte/s). Like I said this link worked for a 10 years like this.

I managed with grooves to pull out site1 -> site2 file transfer 4.5Mybe/s - 5.1Mbyte/s, site2 -> site1 only about 500-800Kbyte/s. Antennas are OK because I swap them between site's, groove's are OK because I swap them between site's also. I am sure that I made correct setup in ROS (I have good speed from one side). ROS version is v6.30.2.

Noise on both site's is from -95 to -98. I also played with noise trash hold, no success. I am sure as long RX signal at site1 is pulsing up-down my link will not be stable. Something is killing only reception at site1, groove is affected by that but WL-5460ap is NOT. How that can be?

Frequency which I used on WL-5460ap I also using on groove's! So at this moment link with WL-5460ap worked much stable than with new grooves.

So question is why on the site1 I have very poor reception but great transmission?
On site2 I have no problems at all.

Any idea?

After some investigation, we found out that mobile phone tower which is right in the path of p2p link is making problems with groove which have poor reception. Problem is as groove have very wide LNA filter. So even as groove is set work on 2.4Ghz, LNA filter is working also at 5Hhz to. Mobile tower using frequency 1800Mhz but if you multiply that frequency with 3 we will get 5400Mhz which is in LNA range. Because signal at 5400Mhz is to strong that makes LNA to become saturated and reception will be very poor. LNA is trying to come back on line but at soon as detects strong signal at 5400Mhz goes off line again. That makes signal to going up and down (pulsing) at 2.4Ghz which I am using. In this case you will have good transmission but poor reception at location where LNA is saturated. Same goes for data transfer of course. We would not have this problem if groove has two filters one for 2.4Ghz and other one for 5Ghz so when we select in ROS frequency range which we want to use only correct filter should be activated.

Sad thing is that I did not found any information about this before I bought grooves. I did not found any warring or any information that grooves will not work if you have mobile phone tower in the path or near by of your location