. QST . he power out-put is taken between grid and plate. Powersensitivity is very low and if plate-filament feed-back can be kept to a minimum no neutralizationis required. This means that the input circuitmust carry the regular filament current in addi-tion to , and ordinary bandswitching of theinput is not desirable. To conserve space, theamplifier to be described was designed for 40, 20,15 and 10 meters onl3^ The main filament coil (adual winding) is used alone for 40 meters and theother coils are switched in parallel to cover thehigher frequencies. The 52-ohm input link iscoupled to t
. QST . he power out-put is taken between grid and plate. Powersensitivity is very low and if plate-filament feed-back can be kept to a minimum no neutralizationis required. This means that the input circuitmust carry the regular filament current in addi-tion to , and ordinary bandswitching of theinput is not desirable. To conserve space, theamplifier to be described was designed for 40, 20,15 and 10 meters onl3^ The main filament coil (adual winding) is used alone for 40 meters and theother coils are switched in parallel to cover thehigher frequencies. The 52-ohm input link iscoupled to the filament coil only, and need not bevaried over the different bands; however, somesystem of changing the coupling between thedriver tank and coax line should be provided. Theinternal antenna coupler in transmitters like theCollins, or a pi-section in the driver output, isentirely satisfactory. The amplifier output circuit will match a 52-ohm line. A 9000-volt tank condenser was found 304-TH )h-r^WpyW-r.
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectradio, bookyear1915
