Ssb Receiver For 20 And 80 M

EE Ell November 1987 SSB RECEIVER FOR 20 AND 80 M The 80 m band extends roughly from 3.5 to 4.0 MHz, and its propagation characteristics enable "local" communication over distances up to about 1,000 km. The 20 m band (14 to 14.5 MHz) is ideal for global communication, provided the right "paths", i.e., tropospheric propagation modes, are available and "open". Very long distances can be covered using low power transmitters, but some knowledge is re- quired of the maximum usable frequency (MUF) in the direc- tion of reception at a given local time. Sections of both the 20 and the 80 m band are assigned to radio amateurs, but the exact band limits are not the same through- out the world. Actually listening to radio amateurs and utility stations in these bands is undoubtledly the best way to learn about their pecularities as to optimum propagation conditions for dif- ferent regions of the world. The receiver discussed in this article is a straightforward design, with manual control. Bl...