What is the purpose of the receiver IF Shift control?

The IF (Intermediate Frequency) Shift control is a powerful tool used to combat interference from nearby stations. It allows the operator to electronically shift the passband of the receiver's IF filter slightly up or down in frequency relative to the tuned signal. By adjusting the IF Shift, you can physically move the filter's edges away from a strong interfering signal on an adjacent frequency. Importantly, this slices off the adjacent interference without changing the pitch of the desired signal you are actively listening to. It is easy to confuse this with a Receiver Incremental Tuning (RIT) or Clarifier control, which changes the actual receive frequency and pitch of the signal. The IF shift keeps the received signal centered in your audio but shifts the 'window' of the filter around it.