THE DESIGN AND DEVELOPMENT OF ONE-HALF WATT HEATER POWER REDUCED SIZE NUVISTOR TRIODE

Samples of the type A15200 nuvistor triode were made and subjected to rather extensive evaluation. Heater power was fixed at 450 milliwatts although operation at much lower heater inputs is possible with reduced ratings. Small-signal RF amplifier measurements indicated very good performance with optimum noise factors below 10 db at 900 mc. Evaluation in oscillator circuits showed the type A15200 to be exceptionally stable with respect to applied voltages and the samples demonstrated good uniformity from tubeto-tube. The electrical performance of the type A15200 makes it applicable to low plate voltage supply service. Vibrational tests of the A15200 showed noise outputs at three regions in the spectrum due to heater bounce, cathode structure resonance and grid resonance but these outputs are not considered excessive. Life tests indicate a probably 1000 hour life with the present processing methods. (Author)