The box on the left contains the low-noise amplifier (the smaller yellowish box) for receiving signals on UHF (437 MHz) and a filter (larger yellowish box) to eliminate interference from the uplink transmitter, mobile telephones and FM broadcasting stations. The black device is a surge arrestor to provide some protection against lightning.
The box on the right contains a low-noise amplifier and bandpass filter for VHF (146 MHz). This unit can be switched on by activating two coax relays. In this way the uplink antenna can also be used to receive satellites that use this frequency band for transmitting data to the ground. Normally, for MIST, this amplifier and filter is not activated.