Having to manually select networks For typical SIM cards, a phone or GSM module can scan all available networks, however it will only try and connect to those for which the SIM is authorized. That is because these type of SIM cards have steering – the SIM card can instruct the phone / GSM module […]

UK Coverage O2 coverage map

Mobile IoT Deployment Map https://www.gsma.com/iot/deployment-map/ Connection Options NB – Narrowband Very limited data limit. Intended for very small amounts, like smart meters etc.Better global coverage LTE-M Better for more data, but not currently forced as part of the 4G spec, so you’re down to which carrier decides to support it in each country. In theory […]

GSM Character Set SMS messages use a different character set to standard ASCII. Characters are 7bits and packed into 140 bytes, giving you up to 160 characters (7 x 160 = 1120 bits, 1120 / 8 bits per byte = 140 bytes). Conversion to and from various ASCII characters needs to be performed in code […]