Apparatus for testing microwave radios having a 35 mhz if using test equipment designed for 70 mhz if

Abstract From the Canadian patent

APPARATUS FOR TESTING MICROWAVE RADIOS by, Larry Y. Onotera and Leonard Dueckman Abstract of Disclosure, A 70?.DELTA. MHz sinusoidal test signal from a standard radio link test set is down converted and shaped to obtain a 35?.DELTA.f/2 MHz sinusoidal test signal to be applied to the radio set under test. The output of the radio set is applied to an up converter in which a multiplier is used that maintains the amplitude lnformation as it doubles the frequency. The 70?.DELTA.f MHz test signal from the up converter is then applied to the input of the radio link test set, and the characteristic is measured as if the radio set under test employed a 70 MHz IF rather than a 35 MHz, IF.