If the main WiFi modem is a long way from the smart TV , too far for a booster midway, is it possible to buy an extra booster so that the signal goes from the modem to the first booster then bounced on to the second one from there? If you know what I mean.
Yes it is but if the WiFi modem is on the same ring circuit (your electrics) you might find a powerline plugs to be more reliable.
Simply plug one in to the modem socket and plug the modem in to that, then plug the other one in to a socket near your tv. Make sure you buy a power plug with wifi ability like these. Cheaper ones are available
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We use Powerline and they are great!
one at modem, one on tv and one upstairs in the "office" by the PC.
At my daughters too. She has 3 stories so one by the modem and the other wayyyy upstairs in the bedroom for TV.