The device contains high linearity, low noise amplifiers, quadrature mixers, plus an on-chip oscillator, operating between 350MHz and 500MHz, which may be synthesised via the differential prescaler outputs. An AGC with 18dB gain control is provided to cope with a wide range of input signal levels. I and Q outputs are via low impedance single ended amplifiers. These may be connected to a dual channel analog to digital converter such as the PCA916, VP216, VP215 or VP213, via a suitable anti-alias filter.