Wi-Fi problem. MCS Index only 7, transnmit rate 73

Discussion in 'MacBook Pro' started by OskarsRacevskis, Sep 4, 2015.

  1. OskarsRacevskis macrumors newbie

    Joined:
    Sep 4, 2015
    #1
    Hello!

    I have been looking all over internet to find a solution to my problem, HOPEFULLLLY actually talking about it will help.

    I have ISP 100mbps and it's very stable, can't complain, yet my speedtest.net results show download speed 45 to 50mbps download and above 50mbps upload. I called my ISP and a guy came with DELL laptop running Windows, for him it was 65mbps d/l and 89 u/l. OBVIOUSLY the problem is in my MACBOOK PRO RETINA 15" Early 2013 running on Software OS X 10.8.5. My Transmit rate is 73, MCS Index is 7 (numbers taken from cmd + wi-fi dropdown) and when i open wireless diagnostics (same dropdown) and go to utilities, under Info it says my channel width is 20 MHz but under Wi-Fi scan it says 40 MHz.

    I have read that transmit rate a.k.a Link Speed (in Network Utility) can go up to 72 mbps if using 20MHz and having one spatial stream (MCS = 7). Also I have read that all Macbooks internal wi-fi cards don't allow use of 40MHz channels. But it should allow more than 1 spatial stream, right?

    I have TP-Link 150 mbps Wireless N Router TL-WR740N. Help please. I've been spending way too much of my time trying to fix this.
     
  2. Kissmyne macrumors 6502

    Kissmyne

    Joined:
    Apr 21, 2015
    #2
    The wifi cards in Macs support the channel widths of the advertised standard, wireless N is 20/40mhz depending a lot on router settings and capabilities.

    Your router model appears to be a single antenna/radio model. The relevance is your maximum link speed(150mbps) is divided by the amount of devices connecting to the device. As an example if i I have 150mbps router with this config, and I connect two devices to it(150/2), assuming they are both active and relatively close to the router they will each have a 75mbps connection(~+/-). Distance used, and the interference to overcome can be additional factors. Download/Upload speed cannot exceed the established link speed.

    How many devices are serviced by your network?

    With regard to the tech that came out with his PC to test your connection, what actions did he perform? Were your devices connected to the network during his testing of your network? Is QoS enabled on your router(if applicable)?

    When testing with Speedtest, did you test against 3 different server offerings(speeds will vary greatly depending on the selection, and the auto select option isn't always the best option)? with same results? Did the tech do this as well? What time of day did you test? what time of day did the tech test?

    Do you have an ethernet adapter? if yes, how are the link speeds? d/l or u/l speeds?

    Do you have a hotspot capable smartphone? if yes, does the issue occur with that device as well?

    Does this issue occur with ANY other wifi network?

    Is your SMC firmware up to date? EFI Boot ROM up to date? https://support.apple.com/en-us/HT201518

    As a side note, the wifi dropdown while holding option will show you current link speed, where as tools like network utility typically report link speed as of establishment of the network(max speed you will have on the connection given current network circumstances when the connection was established)

    FYI I am not trying to discredit your efforts at diagnosis, but in order to help you out with something like this, details matter.
     
  3. OskarsRacevskis, Sep 4, 2015
    Last edited: Sep 4, 2015

    OskarsRacevskis thread starter macrumors newbie

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    Sep 4, 2015
    #3
    Thanks for Your reply. I will try to explain as clearly as i can.
    Here's where i got the info (this image is from Wikipedia)

    [​IMG]

    I read it on this
    site http://appleinsider.com/articles/11...ps_wifi_on_2011_thunderbolt_macbook_pro_imacs

    Reading your reply i realised i have an old HTC phone, which i don't use for browsing internet or anything regarding internet at all, connected thtough WIFI to my Router as well. I switched the connection off now, but nothing has changed for my Mac.
    While the speedtests were done by the Tech guy, it was probably connected. I cannot be 100% sure, because it tends to switch off by itself, i mean its an OLD HTC phone :) Tech guy first connected his laptop through Ethernet port, getting around 98mbps download and upload speed, reassuring me, that the ISP is actually providing me with 100mbps. Then he switched to WIFI, and achieved 65mbps d/l and 89 u/l. At the moment of measuring, my laptop (as well as my phone) was on and connected to internet via WIFI. My guess is, his numbers could have been even higher, if my Mac was off during the measuring (i don't think phone has any impact on this, because well firstly.. its old and i am not using internet on it; if it would have had impact on it, then the Tech guy would have not be able get more than 50mbps, right? Because of the 3 devices sharing the 150mbps router...) While his laptop was connected to my WIFI, i did a speedtest on my Mac and had the same around 50mbps results as i had without his laptop being connected.
    To answer the rest of the questions:
    I don't know if my router has QoS applicable, it is not a very expensive one, but frankly i doubt that is the issue.
    We did speedtests on the best available server www.ping.lv. He did not do a speedtest on speedtest.net, I did but for my Mac the results were identical so i assumed his would be as well.
    I dont have Ethernet adapter
    My phone is old, it might have this hotspot option available, but it was definatley not ON.
    I recall my speedtest results being very similar with my old ISP who also provided 100mbps ( i moved to another appartment).
    My EFI Boot ROM is not up to date. Do You really think this security update could solve this??

    My follow up questions, if i may:
    Are you 100% positive that My Early 2013 Mac Wairless card support 40 MHz channel?
    Where can i see in my Mac if am using 20 or 40 MHz channel atm?
    Looking at the pic above, do you You think MCS Index is important? Why is my MCS Index only 7? What is Your number?

    Thanks,
    Kind Regards,
    Oskars
     
  4. Kissmyne macrumors 6502

    Kissmyne

    Joined:
    Apr 21, 2015
    #4
    I'm not sure you understood my example of link speed division, the math only applies if the circumstances are exact(Distance, signal output, interference etc... and also assuming 1x1 radio configuration), also it sounds like your HTC phone is not a factor here.
    MCS index doesn't matter all that much(most of this will be transparent and your connection is so straight forward that its value is limited). My MCS index is 8 on a Wireless AC connection running at a link speed of 1000mbps, with a channel width of 80mhz(you can find this on the "Scan" section of Wireless Diagnostics, scroll right...). In the scan section if the width shows as 40mhz transmitting, then that is the link width required to establish the connection, this is specified on the router broadcasting, not on the device connected(in order for the device to connect it MUST be capable of establishing that link width, whether one or multiple streams, but that would be a transparent process and would not be the devices issue short of outright hardware failure)

    Have you changed the location? (System Preferences>Network>Location)The name of the location won't matter but if there is a system configured limitation this will typically resolve it.

    Looking at the same wiki article that you screenshoted... "Assuming equal operating parameters to an 802.11g network achieving 54 megabits per second (on a single 20 MHz channel with one antenna), an 802.11n network can achieve 72 megabits per second (on a single 20 MHz channel with one antenna and 400 ns guard interval); 802.11n's speed may go up to 150 megabits per second if there aren't other Bluetooth, microwave or WiFi emissions in the neighborhood by using two 20 MHz channels in 40 MHz mode. If more antennas are used, then 802.11n can go up to 288 megabits per second in 20 MHz mode with four antennas, or 600 megabits per second in 40 MHz mode with four antennas and 400 ns guard interval. Because the 2.4 GHz band is seriously congested in most urban areas, 802.11n networks usually have more success in increasing data rate by utilizing more antennas in 20 MHz mode rather than by operating in the 40 MHz mode, as the 40 MHz mode requires a relatively free radio spectrum which is only available in rural areas away from cities."

    Do you have Bluetooth on? if yes, try without bluetooth..

    I would recommend doing the Boot Rom update as even if the latest version is "only" a security update, you could be more than one increment behind and one of those increments may have addressed "other" issues(I am not going to review each one to tell you the whats new, much less time spent just making sure you are running the latest).

    Regarding your band-width question.. Yes I am certain as it is part of the specification, in order to be a "Wireless N" it MUST be capable of 20/40mhz modes .

    Image attached shows where width is listed in the Wireless Diagnostics Scan window.. Screen Shot 2015-09-04 at 5.43.54 PM.png
     
  5. OskarsRacevskis thread starter macrumors newbie

    Joined:
    Sep 4, 2015
    #5
    I installed the update. No changes.

    Here are the Network Diagnostics Scan window

    Screen Shot 2015-09-05 at 3.21.52 AM.png

    This is Network Diagnostics Info tab
    Screen Shot 2015-09-05 at 3.23.00 AM.png

    See my confusion about the Width?
     
  6. OskarsRacevskis thread starter macrumors newbie

    Joined:
    Sep 4, 2015
    #6
    I don't have my bluetooth on.

    Under Locations I have Automatic. It is the only option.
     
  7. Kissmyne, Sep 4, 2015
    Last edited: Sep 4, 2015

    Kissmyne macrumors 6502

    Kissmyne

    Joined:
    Apr 21, 2015
    #7
    Hold option and click on your wifi menu... should show something similar to this... look at the width in the channel line.

    Screen Shot 2015-09-04 at 8.08.39 PM.png

    To be very clear about what I was saying about location, I was saying create a NEW location(Automatic is default, and arbitrary, you could create another called "manual" and it would work the same). System Preferences>Network>Location> Edit Locations, Hit the +, name it whatever you want, hit ok, make sure it is selected... if applicable hit apply after setting your new location... here are some images for reference..
    Screen Shot 2015-09-04 at 8.14.20 PM.png Screen Shot 2015-09-04 at 8.14.38 PM.png

    Restart after doing this for the sake of argument. (My general school of thought with computers is to give them as few reasons to mess up as possible.)
     
  8. OskarsRacevskis, Sep 5, 2015
    Last edited: Sep 5, 2015

    OskarsRacevskis thread starter macrumors newbie

    Joined:
    Sep 4, 2015
    #8
    Screen Shot 2015-09-05 at 12.03.40 PM.png

    I am using Mountain Lion. I didnt upgrade to Yosemite for the reason they asked me my Bank Accaunt information. I think that's just too much info to give out. Btw if anyone knows how to install Yosemite without giving this info, let me know, i am willing to try.

    I created a new location. Did nothing.

    My theory is that i am using one stream (suggested by MCS Index number) For 11ac, it is different.

    [​IMG]

    Do you know how many spatial streams You are using? I think one. same as me, clearly. Is there a place in Mac to look at the actual spatial stream number in use?

    This is an excerpt from TL-WR740N manual:
    Screen Shot 2015-09-05 at 12.18.31 PM.png

    So.. my Router supports multiple streams. Does my WIFI card as well? Or am I looking the wrong direction here..? Because for me it seems a matter of just finding a way for MCS Index to go to 15. Which is to say, find a way to enable second stream. OR other option: stay in MCS 7 one stream config, but Enable 40 MHz wide channel. Because my Link Speed 72 is the number in MCS 7 row and 20MHz column.
    Screen Shot 2015-09-05 at 12.54.20 PM.png

    Also my Router's Firmware is out of date. Should i update? Is it safe? i should probably do a backup before...
     
  9. priitv8, Sep 5, 2015
    Last edited: Sep 5, 2015

    priitv8 macrumors 68030

    Joined:
    Jan 13, 2011
    Location:
    Estonia
    #9
    You need to switch to 5GHz band! AFAIK, Apple AirPort cards support only narrow channel (20MHz) in the 2.4GHz band.
    http://networkengineering.stackexch...nly-uses-20mhz-of-a-40mhz-2-4ghz-wifi-channel
    http://mailman.nanog.org/pipermail/nanog/2015-June/076341.html

    I personally have given the 5GHz wifi a different SSID to make sure my MacBook always prefers this one over the 2.4GHz.
    MBPro supports 3 spatial streams. But you will need to sit quite close to the basestation to achieve 450Mbps wireless speed on N.
     
  10. OskarsRacevskis thread starter macrumors newbie

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    Sep 4, 2015
    #10
    Thanks, that is not an option for now.
    I want to make the best out of what i have now. And i am getting merely a half of it.

    If my Wifi card supports 20 MHz channel on 2.4GHz band, i need to find a way to make 2 spatial streams, right? Anybody? :)
     
  11. priitv8, Sep 5, 2015
    Last edited: Sep 5, 2015

    priitv8 macrumors 68030

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    Estonia
    #11
    I don't follow your idea here, how would you do this? By adding second wireless card to your macbook? Actually you may be able to find a USB-wireless stick that supports wide channel on 2.4 band.
    But at the end of
    the day, you should ditch the 2.4GHz band as it is overcrowded anyway. (you can see the situation at my location from the attached pics)
    And the whole 2.4 vs 5 vs MIMO setup mess is making it really hard to pick a wireless router just from the specs of it.
     

    Attached Files:

  12. OskarsRacevskis, Sep 5, 2015
    Last edited: Sep 5, 2015

    OskarsRacevskis thread starter macrumors newbie

    Joined:
    Sep 4, 2015
    #12
    Well, my Router supports multiple data streams and my device supports multiple data streams. I don't see where is the problem. Just a matter of enabling, isn't it?

    Btw i Updated my Firmware to latest version.... nothing.
     
  13. OskarsRacevskis thread starter macrumors newbie

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    Sep 4, 2015
    #13
    what is the program You are using in the picture? Maybe it can help me tweak some things.
     
  14. Kissmyne macrumors 6502

    Kissmyne

    Joined:
    Apr 21, 2015
    #14
    As was mentioned in one of my posts, 40mhz modes(including Multiple Spatial Streams) on 2.4ghz are established if there is minimal interference in the spectrum you are using... I.E. if your router is running at 2.4 ghz in a signal crowded area such as an apartment... its probably not going to happen..

    Updating to Yosemite is a sinch, if you are concerned about putting a CC on App Store(essentially same as using iTunes), get a prepaid card, and then remove it before you proceed with the transaction(downloading Yosemite for free)

    My recommendation is to get a better router for your setup(supports 5 ghz). Best of luck.
     
  15. OskarsRacevskis thread starter macrumors newbie

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    Sep 4, 2015
    #15
    right... thanks .. i guess. same to You. Thanks for Your time!
     
  16. priitv8 macrumors 68030

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    Jan 13, 2011
    Location:
    Estonia
    #16
    Wi-Fi Scanner
     

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