Cited as a reference · for some experience
ESP8266 Wifi Range/Distance Tests (Wi07C)
Why people recommend it
CNLohr tests ESP8266 Wi-Fi range, including with an external antenna; cited as a benchmark when people's modules perform worse than expected.
Watch for: external antenna may exceed legal power limits
In their words
As for the range on the device, I have successfully tested the ESP01 over short distances (~150ft) but do checkout this video.
Shreyas Murali on raspberrypi.stackexchange.com, Sept 2016. CC BY-SA.
Here's a vid for moding the chip you have: [video] by adding an external antenna.
Hunter Akins on raspberrypi.stackexchange.com, Apr 2018. CC BY-SA.
