Hello
I'm trying to establish a radio link between 2 points in a highly congested urban area with a lot of radio frequency noises . the distance is roughly 30KM and they're already connected using 2 RB411AH ( Old Equipments ) with 25Dbi Dish antenna
right now the signal is around -70 at best but I want a much faster and more stable link I was thinking to get a pair of Netmetal5 but after seeing NetMetal ax I don't know which one is a better choice
there is even NetBox 5 ax which I'm also interested in is this any good ?
I won't need more than 300Mbps but I need the link to be stable at all cost
I'm also considering using the same antenna for the new radio , is it alright ?

802.11 uses CSMA/CA, which means that if a transmission is detected just 3 dB above the noise floor, your equipment will stop transmitting. Unfortunately, MikroTik does not allow us to disable this feature, despite one of their main selling points being that they let us do whatever we want with our equipment. I'd stick with Nstreme or NV2 since they don't use CSMA/CA. If money is not a problem, I'd get 30 dBi dual-polarity dishes.

Are you using DynaDishes ? What protocol are you using right now? Nstreme? NV2? 802.11? Have you tried changing?

By the way, I ran a calculation and find it strange that you get -70 dBm given a 30 km distance and 25 dBi dish. It suggests that you are emitting at 40 dBm. I assume a 2 dB cable loss, so you probably set TX power at 17 dBm. If that's not the case, then another possibility is that the antennas are misaligned. There could be a directional misalignment; often antennas don't point straight but slightly to the side. There could be a small polarity misalignment, so I'd try turning the dish to check for that. Or perhaps that particular antenna performs poorly at that frequency, try moving to a different channel. Maybe there is more moisture in the air than normal. Maybe you are getting multipath interference; I'd try moving the antenna forwards or backwards (or upwards/downwards) by just 1 or 2 centimeters. Or many other factors.

P.S. Higher positioning is not always better. Ideally, you'll position the antennas so that you get only one multipath reflection and so that the interference is constructive, not destructive. Although it's hard and time consuming to achieve.

thanks for the reply
the alignment is ok and I have already tried increasing the output power but nothing changed
can it be a hardware issue ? the radios are pretty old

30KM, urban, with a lot of noise , -70dBm signal levels and you want "no more than 300mbit"?
get real.
maybe with 34dBi dishes and high power radios you might get something close to 200mbit.

30KM, urban, with a lot of noise , -70dBm signal levels and you want "no more than 300mbit"?
get real.
maybe with 34dBi dishes and high power radios you might get something close to 200mbit.

Yup, 300 Mbits at -70 dBm is total fantasy.
I shouldn't have wasted time replying, especially given that he answered none of my questions. Feels like being trolled TBH.