Fuel Price Monitor With GSM Shield

This is my Fuel Price Monitor, a refreshing anachronism in the times of electric cars.

It comes in a retro design, featuring a 4-segment ticker where some predefined gas stations and the associated fuel prices are shown and it is controlled with one big illuminated arcade button.

Technically it consists of a D1 Mini, that is connected to a gsm module for internet connection.

With a short press on the arcade button the ticker switches between two regions. A long press starts a manual update. Otherwise the script does an auto-update every 15 min. The database I use is https://creativecommons.tankerkoenig.de/, but also other databases with an API are conceivable.

Other features are a light sensor, that dims the display at night, a loop through usb connector to charge the smart phone, an outer case with a rail system, to mount it in the car and an on-off switch. Also there is still enough space to place your smart phone below.

List of Parts:

• Wemos D1 Mini
• SIM800L V2.0 5V Wireless GSM GPRS MODUL
• 2000 µF ELCO as replacement for the too weak on the SIM800L module (yellow)
• TM1637 4-segment display
• LED Arcade Button + 220 Ω resistor
• USB Type-A Connector Breakout Board
• Micro Switch
• Photoresistor + 10 kΩ resistor

Additional tips:

• Don't use PLA Filament unless you want a melt down in the summer.
• To glue the outer case in the center console use e.g. Powerstrips
• Replacement of the SIM800 resistor