Slow transfer rate when using a ralink 3070 through USB as WISP


I just got a GL-MT300A and setup has been pretty easy, I’m running a similar setup as this other post: wifi adapter in usb AR-150

My set up:

Ralink 3070 Long range USB adapter: Card King KW-3016

(this is self powered card and connected to a 2A usb power adapter.


Radio 0 is set up as Master with a new SSID for my LAN

Radio 1 (usb adapter) is set up as client connecting to wifi network as WISP.


My Problem is the wifi performance. When using LAN wifi a speed test will show 1-3Mbps but if I switch to ethernet using the Lan port the same speed test will reach 15-20Mbps (my ISP speed)


Any help will be appreciated it


when you use 3070 as a repeater and use LAN cable, the speed is 15 to 20Mbps?

I have a very small 3070 and tested with MT300A board.

When 3070 acts as repeater, I got D25.4, U19.75 from LAN port and D9.78 U2.28 from wifi.

When I use MT300A solely working as repeater and ap without 3070, I got D44.42 U46.57 from LAN port and D27.23 U14.43 from wifi.

Using MT300A solely as repeater works much better. I still don’t know why an extra 3070 works no good. But you can just use without it.

Ok. I tried again.

3070 was set as 11g. Now I set it as 11ng and HT40, I got D14.00 U2.68, which is a little better

I reverse the two radio and tested again, speed is even lower.

So, seems one radio is better than two. Especially the 3070 is not good at AP.


At one point, on another device, I also had slower speeds using a USB device as a second radio. Someone suggested that putting the USB radio on an extension cable would improve the speed, which implied some type of interference. Ultimately I replaced the USB with one that had a larger antenna. It improved the speed, but it was not as good as the single radio.

Thanks for the response. Yea I tried the router without the USB card and just as a regular router mode and speed test is pretty good.(although I never got a link speed of 300Mbs just 150Mbs)

so it seems the issue happens when two radios are connected at the same time.

Anyway this can be fixed with a FW update?

Just to be clear, link speed is not a speed test. Your link speed is also dependent on the STAtion\client you are connecting to, as well as the channel width for your MT300A. You may also have different link speeds for each radio or connection. There is also an up and a down link speed, for a total of 4 values.

Use the Advanced Config (Luci) and go to Network=>Wireless. Choose Edit for one of the wireless connections. (One will say linked to …, use the other). Set the channel width to 40 from 20, if it’s not. The devices at the other end should have similar configurations to get the best “link speeds”, or the MT300A will run at the lower of the 2 speeds (at best). Link speed will probably fluctuate.

Did you try the USB key on an extension?

For your speed test use either (IF you have a choice of test locations try to be consistent)

Internet Speed Test – AT&T Official Site (personal preference)


for using 2 APs on 2.4GHz these are expected results. i would suggest to get atheros device like tp-link TL-MR22U because ar150 is crap and i wouldn’t expect much more from ar300 too, and run it’s wifi on 2.312GHz, then you will get good speed with rt3070 on any of the 1-13 channels. otherwise be happy with 5-10Mbps speed.

I understand link speed vs speed test. I was just making a side comment about the router performance itself while in a normal application. At this point I’m going to try a different openWRT device. I just ordered a D-Link DIR-860l . Thanks for all the feedback.

@psyborg, be nice! If you have problems you can solve with us. And we did ask you send us emails so that we can help. I think what you are saying is that AR150 can output more power in its USB-A port. Why that is a bad design? You are saying that it causes the router to boot because the external device is using too much power. But as USB2.0 specs the USB-A can only output 500mA. So is that enough to power up your USB device. You should also notice that a battery can output more current than a power adapter.

@stakil4 maybe you can set the 3070 and MT300A to two differnet channel such as channel 1 and channel 11.Maybe it will better.

The reason is the antenna can receive signal from the air,and if you put a wifi device beside it,it can receive more signal with high signal intensity which may

affect the device who is in use.and the MT300A wifi will affect the 3070 wifi too.