I have admittingly not cheap circa £700 Netgear Nighthawk M6, partnered with its relatively inexpensive add on Ariel.
Nighthawk M6 WiFi 6 Mobile Hotspot 5G Router - MR6150 - NETGEAR
Since I have had it we have not had issues getting decent signal anywhere when we have been away (Places we have been since getting it: Lake District, Yorkshire Moors, North and South Wales, and remote parts of Perthshire). This includes a number of times when our phones have not had signal yet this thing has produced more than 20mbps minimum. Seen it produce over 300mbps on 4G and over 700mbps on 5G.
It uses a thing called Carrier Aggregation which is a technique used to increase the data rate per user, whereby multiple frequency mobile blocks are assigned to the same user. Meaning using one sim card it asks for the same data across multiple frequencies and then combines them together, to give increased reliability and ultimately speed.
I keep the main M6 in cupboard velcroid to the side out of the way, the add on Ariel then sits on top between cupboard and upper bed board, Occasional if the signal is not great I have let the Ariel hang down vertically over the cupboard, as signals are directional. This change has then resulted in improved coverage.
Originally I had planned to get a roof mounted GSM shark fin, but do not see the need now, as the current setup has performed without flaw.
The kids stream as we are driving and not had any drop out the whole time we have used it, and drive through a lot of black spots. I have used the M6 on its own on the train from Aberdeen to London for work, and noticed no issues- normally have issues using just hotspot on phone or using the train wifi.
In it I use one if the pre-paid preloaded sim cards - which over the time equates to about £12/m for unlimited data.
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