now to find that special frequency.
Also, is there a way to easily upgrade router os and install the rep package without doing 1 radio at a time?
Once you have surveyed the radio spectrum for other stations and interference/noise, you may have an answer as to why your radio system is operating so badly. If using the default settings that are already there from MikroTik factory reset and just changing the very basic settings such as SSID, security to make a link does not improve the operation of it, then you have a spectrum issue. No changes to the config will improve it that much, as you are already at a very slow speed. So, if a reset of wireless settings (you can reset the wireless with a single button without losing all other config settings on RouterOS) does not make this operate much better, spend more time looking with spectrum analyser and using scan tools to identify the cause and hopefully, a better / quieter radio channel.
nest is totally correct
a clean clear frequency/channel is very important to fast throughput.
It is important and pretty easy to perform a site-survey and a frequency usage on the AP (assuming you do not connect to the AP through the wireless network)
It is also important and however not-so-easy to perform a site-survey and a frequency usage on a client connected device - because you will disconnect when you begin the scan. There is a trick to performing a scan to a remotely connected client - here is the procedure (works most of the time):
#1 from your computer , TELNET to the remote client Mikrotik (TELNET - not ssh or winbox or http).
#2 change into /interface wireless
#3 type or paste this in (for a client frequency usage report):
/interface wireless frequency-monitor wlan1 duration=10
#4 wait about 10 to 15 seconds (do not type anything)
#5 type or paste this in (for a client site-survey report):
/interface wireless scan wlan1 duration=10
#6 wait about 10 to 15 seconds (do not type anything)
A frequency usage report will look something like this:
FREQ USE NF
2412MHz 15.7% -96
2417MHz 4.9% -97
2422MHz 1.1% -96
2427MHz 0% -97
2432MHz 0% -98
2437MHz 1.8% -98
2442MHz 0% -98
2447MHz 0% -99
2452MHz 0% -99
2457MHz 4% -99
2462MHz 1.8% -98
A site-survey report will look something like this:
ADDRESS SSID BAND FREQ SIG NF SNR RADIO-NAME
ABPR 00:15:6D:65:AD:2E Red-Spectrum.com 2.4ghz-g -96 31 MicaWA-facing-SE
ABP 00:1F:33:DB:8C:33 Netgear 2.4ghz-g 2437 -87 -96 9
ABPR 00:15:6D:65:FA:3B Red-Spectrum.com 2.4ghz-g 2457 -89 -96 7 MicaWA-facing-SW
AB 00:1C:F0:F4:CE:FC Timberhouse 2.4ghz-g 2462 -81 -96 15
Now you can find a clean clear frequency for your AP and know it is also clean/clear for all of your clients also.