In a simple 2 stage CW transmitter, current to the collector of the transistor in the class C amplifier stage flows through a radio frequency choke (RFC) and a tapped inductor. The RFC, on the tapped inductor side, is also connected to grounded capacitors. The purpose of the RFC and capacitors is to:

An RF Choke (RFC) placed in series with the DC supply line, combined with capacitors shunting to ground, forms a classic LC low-pass filter. This specific arrangement acts as a decoupling network for the power supply. The purpose of this low-pass filter is to allow low-frequency direct current (DC) to reach the amplifier while presenting a high impedance to radio frequency (RF) energy. The shunt capacitors then route any residual RF safely to ground, preventing it from feeding back into the power supply and causing instability or unwanted emissions. This network is strictly for power supply decoupling. It is not an RF-tuned circuit (which would select a specific resonant frequency), a key-click filter (which shapes the envelope of a keyed CW signal), or a negative feedback network.