These show views of the logger

Front:Front view
Top with lid open.The receiver on the left is on the end of a cable to isolate it from interference. Its lid is not shown.
On the top left is a circuit to encode the four arrow buttons into a single analog value to conserve pins on the Arduino, which is hidden below the logger shield.
The board in front of the Picaxe board houses the analog input attenuators.
The other vertical board houses the attenuator for the charging voltage. Top virw
The battery is charged from any supply from 5-24V
The switch cuts off battery power as well as circuit power. Power assembly
The Picaxe processor is connected to the RF receiver raw output, and to four analog inputs.
It has an integrate-and-dump circuit to provide an interrupt signal when a message is received. Other parts are for input protection. Power assembly
The Logger Shield plugs on top of the Arduino, which is a Pololu A-Star 32u4, not the regular UNO. It has more memory and runs directly off the battery.

Power assembly