The USB-C connection on the back of the KVD21 (Home Internet), can there be an external antenna attached?

I don’t know if this is true, but an EE friend of mine speculated that the reason there is no external antenna jack may be because the FCC has limits on radiated power these devices are allowed to produce, and an external antenna may put them over the limit. 

Yes Tinkeralot, and I have watched the vids on how to add them, but when your 70+ and little to 0 experience with a electronic type modification, plug and play is the only real option.

I can see the same here. For many users the use of an external antenna would be a significant improvement. The current offerings make it difficult to have a good local wireless signal distribution due to demand on gateway placement to improve the cellular reception. It is possible to add external antennas to the gateway but there is risk involved and additional technical hurdles to overcome. It would really be nice if they offered a gateway with the external connections. Options are always nice to have. 

The ability to have an external antenna would really help my situation

I have seen other cellular routers that do have external antenna connections and a robust feature set, but they are more expensive and T-Mobile would probably not allow the connection to their network. The current “solution” is about control on various levels and limitations on support. It would be nice if they did offer a router with the external antenna connections for subscribers in challenged locations where service could be improved. 

I wish T-Mobile would implement a built-in antenna so we don’t have to open the gateway.

The signal strength is only part of the equation. Look at the cellular metrics in the mobile application. Signal strength is good but you need to know if the RSRP signal quality and SINR noise are also in the good to excellent range. If signal quality is poor and there is noise the performance will blow. External antenna solutions can help improve the signal in many cases. Waveform.com is a good source for information and their technical people are really helpful. 

Don’t negate 3 bars signal strength.  That’s all I can get, but with great down speeds!

There are cellular boosters but they are not designed for such a purpose.  If you want a 5G cellular booster it is not cheap. Cellular boosters for 4G LTE are in the neighborhood of $500-600 for a fairly solid unit. The company weBoost has some fairly well rated cellular booster systems. You need to confirm what the antenna can do with the specific cellular signal you are trying to amplify. You really need a dual antenna solution to get better reception. There are many options out there and some are much better than others. Costs vary widely.

Hi Allan.. Oh, I have watched that video several times but once you take it apart.. you own it. And with the cost of everything over the moon, I don’t want to buy the device. But, is there such a device as a signal ‘booster’ that can bump up the incoming signal and focus it on the internal antennas?