Abstract
The authors have developed an SHF television converter of new circuit structure using a Microwave Integrated Circuit (MIC) module.
A wideband Rat-Race circuit, in which an additional output port is incorporated to eliminate the crossover structure, is employed in the mixer section of this con-verter.
The fluctuation of the Gunn diode local oscillator frequency is stabilized within±297kHz (-20°C-55°C) by implementing an AFC circuit consisting of a dielectricresonator housed in a small oven and a phase discriminator.
The conversion loss of the experimental mixer is measured to be less than 3.9 dB including the insertion loss of the input bandpass filter, and the overall noise figure for 150 MHz bandwidth is 5.2 dB.
