Dear Friends,
I am looking forward to opinions and reviews about a suitable AP for SXT's Freq used to be 5Ghz a/N

1. What I think is most suitable for an AP, is 433AH with R52Hn and dual pol 17/18dbi Sector Antennas.

However there may be some people who do not have dual pol antenna so I would like to know what difference will it make to have single pol antenna connected to the "Main" of R52Hn card.

2. What settings should be enabled if we have dual pol antenna.

3. What settings should be disabled on the SXT client if we have single pol antenna at the AP.

4. Should I have the nearby SXT's enabled at N only and the further ones at A/N

1.) I believe the RB800 is better suited for use as an AP with SXTs.

Why: The CPU is a major factor when dealing with the higher throughput that N offers...even though it's clock is only 120Mhz faster than the 433AH, it's different architecture (PowerPC) and more RAM actually make it almost twice as powerful (see comparison here: http://www.routerboard.com/pdf/RouterBO ... arison.pdf )

Also, the Mini-PCI layout is much better...you can actually get 4 high powered cards in the board with room for heat dissipation.

Using single chain / Pol works but is far from ideal - It's worth mentioning that you don't have to use a dual pol sector - You can use one horz sector and one vertical sector....just make sure they're aligned properly. While not the same setup - I'll say that I was once out of dual-pol dishes - so I used 2 - 26dB grids, one horz and one Vert - pointed to a dual pol dish - it gets 100mb easily.

I can't say that I've been impressed with any card using a single chain - Why?: To really benefit from speed that N offers - signals need to be less than 70. Most of the N cards on the market have relatively weak output through the data rate range. For example the R52HN has an output of 18dB at MCS 7 (65Mbit) when using *both* chains. In my experience the signal degrades far worse than half (3db) when you're only using 1 chain....see examples below.

Access Point is RB800 with SR71-15 Attached to UBNT 16dB Dual-Pol Sector. There are 3 clients connected- 2 are SXT's.

Here are Signal Strengths with Both Chains Enabled:



Here with only Chain 0 enabled. Notice that only one SXT client connected.



Here is a TCP bandwidth test using 20Mhz Channel on the SXT Client that's labeled "3.04 Miles Out"



2.) Refer to my blog post here about how to configure the SXT's with the maximum settings: http://www.wispforum.net/entry.php?5-Ho ... ode-Part-I

3.) De-select the chain that isn't being used on the HT Tab.

4.) Depends on your environment and the signal strengths - I do think it's wise to have the AP set to A/N because there are situations where the only way to get service to the client would be with a large antenna and higher powered card (e.g. XR5).


Hope that helps!

Having too many cards in one box increases the Noise. We try to use one card on one routerboard. As w.r.t. r52hn i was told by mikrotrik support that the power increases with bandwidth demand. So at no load it shows 18dbm but at max load it can go higher to 24/25dbm.

Although this was something i cld not understand why.