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Ripper
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RB751U-2HnD weak wifi

Wed Dec 07, 2011 11:37 pm

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it speed with 300 mbit usb steak 2m from router 40mhz ... 2 chains select WPA2 AES signal

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What's wrong with it distance 1m (-19dmb) i cant reach even speed tp-link 1043nd with 20-25m thrue 3-4 walls ... just two bars in windows signal info (~-76dbm)
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cieplik206
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Re: RB751U-2HnD weak wifi

Wed Dec 07, 2011 11:59 pm

looks like signal can allow you upto 88mbps,

Do you have fast and reliable speedtest.net server ?
 
Ripper
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Re: RB751U-2HnD weak wifi

Thu Dec 08, 2011 12:00 am

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wired
Last edited by Ripper on Sat Dec 10, 2011 11:52 am, edited 1 time in total.
 
cieplik206
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Re: RB751U-2HnD weak wifi

Thu Dec 08, 2011 12:02 am

there is default security profile, and you said AES,

just a note (on TKIP 11.n doesnt work well)

try to use "advanced" rate selection algoritm and redo test
 
Ripper
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Re: RB751U-2HnD weak wifi

Thu Dec 08, 2011 12:08 am

I knew that so i set WPA2 AES
 
Ripper
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Re: RB751U-2HnD weak wifi

Thu Dec 08, 2011 12:13 am

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Advance was set before so I set legacy and disable encryption at all...

Buy that device to replace ADSL modem-router ZTE but as I look that thing don’t worse it....
I want to buy that because I use before 750g nice thing but now I’m disappointed
I buy that device to up 3g connection but even with watchdog script it's very unstable if connection down script can’t bring then alive by shut downing ppp connection or rebooting router helps only unplugging device from power.
Last edited by Ripper on Thu Dec 08, 2011 12:20 am, edited 1 time in total.
 
gnuttisch
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Re: RB751U-2HnD weak wifi

Thu Dec 08, 2011 12:16 am

try to set HT AMPDU 1-3 and then try again. worked well for me.
 
Ripper
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Re: RB751U-2HnD weak wifi

Thu Dec 08, 2011 12:28 am

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with advanced HT AMPDU 1-3
Problem that it's 1m results i bought that device to cover from 2nd floor 3 floor 40-50m building 1W power and so on ...
TP-link has only 100 mW and works much better ... (i haven't tryed it that bulding I've tryed it at home with several walls with reinforced concrete)
It gives me result like G type not N

Can you Upload me you config =) ... wan DHCP other ports LAN bridged + wlan1
bridge with DHCP NAT DNS
 
uldis
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Re: RB751U-2HnD weak wifi

Thu Dec 08, 2011 10:22 am

what data-rates you are getting when you switch to advanced rate-selection?
 
Ripper
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Re: RB751U-2HnD weak wifi

Thu Dec 08, 2011 1:18 pm

form 60/135 to 135/150 noise floor -99 .... tryed distance from 1m to 25-30m (signal worse then 1043ND with transmitter 100mw)
 
Ripper
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Re: RB751U-2HnD weak wifi

Thu Dec 08, 2011 11:09 pm

first of all that device wont connect 300/300 or even 150/150 on ideal conditions -99 noise floor distanse minimum signal ideal -60db ++ .... and I not shure that it works at 1w power ..... first thing that tels me about that that device with 100mw trasmiter show same signal rates but works much better than MT devices.
 
temuri426
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Re: RB751U-2HnD weak wifi

Fri Dec 09, 2011 11:27 pm

hi all
experiencing the same problem , signal from client to AP is very good (in registration RX rate is 65), but from Ap to client TX rate is 1mb, or 5mb ...

this happens when distance betweeb AP and client is about one meter. when i'm far from the AP , client is connected much better.

what can be the problem?
 
Ripper
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Re: RB751U-2HnD weak wifi

Sat Dec 10, 2011 10:02 am

I check that situation by checking thru one wall ... it won't help tried to check thru many walls 2 aps in same position 1043ND works much better as the connection rate and actual download rate ... I can't understam how can it be with 1w transmitter range must much better ...
 
temuri426
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Re: RB751U-2HnD weak wifi

Sat Dec 10, 2011 5:38 pm

Ripper

agree with you , tp link works much better then rb751.. mikrotik's radio is much powerful but doesn't works ok.
 
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zervan
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Re: RB751U-2HnD weak wifi

Sat Dec 10, 2011 6:10 pm

I thought that RB751U will be much better when I connect external antenna. So I did so today (using 5.9). I've made a lot of tests and find out that the best results I can get using:
  • Channel Width: 20MHz - strange, but using 40MHz the speed is not much better and stability is worse (but in fact I can use 20MHz only because I will use multiple access points alternating channels 1, 6, 11, so it doesn't bother me)
  • HT Chains: both (external antenna is greatly improving chain1)
  • Antenna Mode: antenna b (obviously, b means external antenna for chain1)
Bad thing is that I can get higher transfer speed using "common" 802.11n Canyon home router (using 20MHz as well). I've tried transferring data from my NAS to one PC, the same file from NAS to 3 PCs at the same time, measuring speedtest from internet to PC and to multiple PCs - common router is faster in any situation :?

I need RB751U to act as hotspot stations (WiFi AP + hotspot) connecting to central User Manager on RB1200, but now I am thinking about combination of cheap RB750 and cheap "common" AP instead of RB751U. Two cases, two adapters, but better speed?

Bottomline: yes, using external antenna is better than internal, but not good enough comparing to other WiFi routers.
 
Ripper
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Re: RB751U-2HnD weak wifi

Sat Dec 10, 2011 6:42 pm

I ask reseller to get antennas but he say that antenna has not regular port so it is very difficult to find antenna for it ...
...

my 1043ND give's me 90+ Mbits (9,6 Mb/s torrent) thru one wall (ferroconcrete) signal 5 bars but that device gives at 1m 30- Mbits.
 
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zervan
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Re: RB751U-2HnD weak wifi

Sat Dec 10, 2011 7:03 pm

I ask reseller to get antennas but he say that antenna has not regular port so it is very difficult to find antenna for it ...
Yes, indeed! But see this: http://forum.mikrotik.com/viewtopic.php?f=3&t=50602
I've got antenna for RP-SMA and pigtail for MMCX.
 
Ripper
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Re: RB751U-2HnD weak wifi

Sat Dec 10, 2011 7:53 pm

How much it cost half price of that device ? =)
 
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zervan
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Re: RB751U-2HnD weak wifi

Sun Dec 11, 2011 5:19 pm

How much it cost half price of that device ? =)
Adapter is practically impossible to get in Europe, but pigtail costs about 4 USD and antenna 6 USD, so cca 10 USD together.
 
pljubas
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Re: RB751U-2HnD weak wifi

Thu Dec 15, 2011 4:54 pm

...
[*]Antenna Mode: antenna b (obviously, b means external antenna for chain1)[/list]
...
Can anyone confirm that external connector on RB751U-2HnD is actually antenna B?
I would like to use external antenna only on a single chain.

Thx for back information

Petar
 
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TheWiFiGuy
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Re: RB751U-2HnD weak wifi

Thu Dec 15, 2011 8:59 pm

I need RB751U to act as hotspot stations (WiFi AP + hotspot) connecting to central User Manager on RB1200, but now I am thinking about combination of cheap RB750 and cheap "common" AP instead of RB751U. Two cases, two adapters, but better speed?

Bottomline: yes, using external antenna is better than internal, but not good enough comparing to other WiFi routers.
Theres clearly a problem with either the hardware, firmware or settings as Im also having problems trying to run a simple access point using a range of radio cards in the MT. Ive now switched those sites to an engenius plugged into an RB750 and it works a treat.

Maybe someone running a Mikrotik setup as a hotspot / access point could let us know their settings?
 
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zervan
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Re: RB751U-2HnD weak wifi

Fri Dec 16, 2011 10:08 am

Can anyone confirm that external connector on RB751U-2HnD is actually antenna B?
I would like to use external antenna only on a single chain.
Later, I've found this information in manual, too: http://routerboard.com/pdf/357/rb751U-2HnD-ug.pdf - so it is officially confirmed ;)
 
pljubas
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Re: RB751U-2HnD weak wifi

Fri Dec 16, 2011 10:32 am

Can anyone confirm that external connector on RB751U-2HnD is actually antenna B?
I would like to use external antenna only on a single chain.
Later, I've found this information in manual, too: http://routerboard.com/pdf/357/rb751U-2HnD-ug.pdf - so it is officially confirmed ;)
Excellent, thank you.

Best regards,

Petar
 
ddejager
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Re: RB751U-2HnD weak wifi

Sat Dec 31, 2011 5:35 pm

I believe there are problems with the performance of this router. See my posting here: http://forum.mikrotik.com/viewtopic.php?f=7&t=57942.

I've also run a number of tests with an external antenna on this router and also believe that there are issues with it at well. See my posting here: http://forum.mikrotik.com/viewtopic.php?f=3&t=57847

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