High Output Oscillator

Figure 1 

This is a high output oscillator set at 1Ghz. Designed out of frustration of not having a matched PNP transistor. The circuit will deliver 3v RF with the components shown.

If you were to use two 100mW rated transistors, you would obtain around 300mW out.

Tuned circuit is L1,L2,C2,C3. Values chosen for 1Ghz for test purposes.

Two 2N4427’s will deliver nearly 3 Watts out at VHF frequencies.

Good Heat Sinking should be used. L1+L2 can be moulded chokes.

Note: Q1+Q2 Must be ‘Well Matched’ to prevent either transistor from doing most of the work.

Designer & Author: Special thanks to Laszlo Kirschner.