These are highly modular cable TV amplifiers, they are set up by using a wide range of different insert cards with different frequency ranges or options. These are 38 dB amplifiers in the range from 47 to 862 MHz.
This particular amplifier is set up for 862 MHz, 42 channels and has a return path amplifier for keeping signal strength on the line good. The line equalizer is used to adjust for how close to the community amplifier the house is located, the further away, the less attenuation is needed.
These small amplifiers are used in houses where it is not practical to use a receiving antenna to get the signal from the broadcast headend transmitter. They are called a “service drop”
Instead CATV is used, short for community antenna TV, a large receiving antenna is used, a cable connection runs out to every house in the neighborhood and each house has one of these amplifiers. The return path amplifier can also send some of the signal back into the line to keep the signal good enough for the next house.