1 Gc transistor amplifier stage using Linvill technique

Recently, there have evolved graphical techniques to facilitate transistor amplifier design using a sampled parameter approach. Specifically, a method suggested by Linvill??J has found acceptance at VHF and UHF frequencies. Since transistors with useful power gains in the Lband region have become available, it was natural to attempt to extend this technique to the higher frequencies. This communication describes a laboratory amplifier, designed and built using the above mentioned technique. The power gain was measured to be 103 db when the amplifier was tuned for maximum power gain. The load and source admittances that were presented to the transistor were measured on a General Radio immitance bridge and excellent correlation was found between measured values and those calculated from the Linvill approach. This measured noise figure wasf ound to be 8 db (calculated, 7.62 db). From the good correlation obtained between theory and practice, in the above experiment, the Linvill method of amplifier design at 1 Gc has been demonstrated to be an excellent tool in the hands of the design engineer.