The Influence of UHF Allocations on Receiver Design

The principle of affording protection to receivers from adjacent channel interference by alternate channel assignments has been universally accepted. It is shown that approximately 20 db added protection between receivers from local oscillator radiatian can be obtained by alternate channel assignments and receiver intermediate frequency standardization. There is also developed a square assignment plan in which added protection is provided for image interference, the picture image station being spaced 1.4 times the adjacent channel station and the co-channel station 2 times the adjacent channel station. It is shown that 41.25 is the optimum value of intermediate frequency for joint vhf-uhf usage.