Wireless N card help

Hardware MikroTik hardware general
1

Dear guys!
Which are the best N cards to use with RB433 and RouterOS?
Last year I tried R52N but I didn’t obtain good throughput, and last month I tried R52HN with NV2 but I had problem with signal strenght that was about 10 dbm less than signal with R5H.

I think to try ubiquity SR71: is it OK with RouterOS?

Thanks in advance

Best regards

2

if none of the tested cards provided you good signal and throughput - you must be doing something wrong.

3

Hello!
With R52N and even with R52HN I have -62 dBm on tx and rx signal, instead with radio R52H I have -52 dBm using same PacWireless antenna on same position. Why? I think this is a hw radio problem, or not?

This is problem that i had with R52N http://forum.mikrotik.com/t/throughput-and-ccq-decrease-when-traffic-increase-wireless-n/30997/1

Thanks in advance

4

R52Hn’s work perfect in every aspect for me thus far. They are better than the R52N in my opinion.

Check to see if you have periodic calibration enabled/disabled and are not having issues with noise floor / Interference.

5

there is a difference because the cards are very different, even their output power and sensitivity is different!

http://www.routerboard.com/pricelist/download_file.php?file_id=97
http://www.routerboard.com/pricelist/download_file.php?file_id=170

6

Hi!
Where is difference? Is this?

R52H @ 54Mbps @ 20 Mhz → TX Output: 20 dBm Sensitivity: -70 dBm
R52N @ 54Mbps @ 20 Mhz → TX Output: 16 dBm Sensitivity: -77 dBm
R52HN @ 54Mbps @ 20 Mhz → TX Output: 18 dBm Sensitivity: -77 dBm

There is only difference of 2/4 dBm, and so I don’t understand why I have difference of 10/11 dBm on Signal Strength.
If I will try SR71-15 (http://ubnt.com/downloads/sr71_15_ds.pdf), could I obtain best signal strength?

Thanks in advance

Best regards

7

this is a huge difference :slight_smile: please study some more on wireless specs and technology. use some wirelesss link calculator like RadioMobile to make the comparison

8

Hi!
Could you tell me which is the huge difference please?

Thanks

Regards

9

this is huge difference:

R52H @ 54Mbps @ 20 Mhz → TX Output: 20 dBm Sensitivity: -70 dBm
R52N @ 54Mbps @ 20 Mhz → TX Output: 16 dBm Sensitivity: -77 dBm
R52HN @ 54Mbps @ 20 Mhz → TX Output: 18 dBm Sensitivity: -77 dBm

10

Just only 2 dBm, and so why R52N&R52HN signal strenght is 10 dBm less than R52H? It could be about 2 dBm and not 10, or not?

Thanks

Regards

11

If you don’t understand logarithmic scale, then don’t use it.
Convert dBm to mW… for bigger impression

12

OK, but why R52N&R52HN signal strenght is 10 dBm less than R52H? It could be about 2 dBm and not 10, or not?

Thanks

Regards

13

how do you measure it?
You changed the wireless card on one end only?
What values you look at?
Also note the the noise floor value effects the signal reading.
When comparing the signal lock them to one data-rate, for example to 6mbps.

14

Hi!
Thank you very much Uldis.
I change wireless card on both end and I look tx/rx signal strength value on “Registration” tab.

On wireless configuraton I use “Configured” data-rates and I check all “supported rates A/G” and “Basic rates A/G” for wireless card R52H and for wireless card R5HN I check all MCS data-rate to obtain best throughput.

I remember that with R52HN radio, I tried to use “all-rates-fixed” on “tx-power-mode” and tx-power of 20 dBm but signal strenght was always of -62 dBm, instead with R52H was and is of -53 dBm (tx-power-mode=default).

Thanks

Best regards