Hi, It's not able to check the signal strength via that way.

Hi, you can choose 3G only or 4G only for the Network Mode on the routers. MR6400 and M7350 are both Cat 4 products, but MR6400 has external LTE antennas, should be better than M7350 to receive 4G...

Hi, You can check if your dongle in the compatibility list or not. http://www.tp-link.com/en/support/3g-comp-list.html?model=TL-MR3420&hdVer=V3 If not, then they may have compatibility issue. But you...

What's the model of your power bank? What's the issue of it? StevePonti wrote Hi Guys! My power bank also has power fast button but it is not working very well. Can I help me? what is the wrong?

Your printer is not on the Printer Compatibilty list, that means they may somewhere has compatibility issue. http://static.tp-link.com/TPLink_20170419_Printer_CompatibilityList.pdf brackmann wrote Hi...

Yes, the button likes a wifi reset, it turns on/off for both bands.