The 10 meters 27MHz CW radio amplifier is equiped with VN66AF transistor produced by Siliconix wich has some advantages: its cheap, great dielectric insulation and high gain. Here we use VN66AF as an rf amplifier for 10m band (26 … 30 MHz ).
With this 27MHz rf amplifier, small transmitters ~ 200mW, can be transformed in 2 to 3 W 10m transmitters. The band-pass filter attenuates at least 55dB.
For linear applications (AM and BLU) the VMOS FET gate current has to be 20mA adjusted with P1. If we want to use this 10m rf amplifier for FM and CW adjust P1 so there is no current to FET gate. In our case the repose current ( steady current ) is 200mA to 300mA.
VN66AF amplifier circuit components
L1 = 12 turns / 0.6mm / 9mm
L2 = L4 = 5 turns / 1mm / 9mm
L3 = 8 turns / 1mm / 9mm