Abstract: A programmable signal receiver for use in a computer system. The signal receiver is located inside the computer's chassis and has an interface directly coupled to the computer's bus for receiving instruction signals which specify one or more channels to be selected from a broadband input signal. Each selected channel of the broadband signal is amplified using amplifying circuitry of sufficiently low impedance that the RF radiation produced does not interfere with the operation of the computer system. In one embodiment the signal receiver's input port is d.c. coupled to the computer's d.c. power supply so that the computer's d.c. power supply can be used to provide power to apparatus external to said computer system--such as a satellite dish's feed horn.