Tuned amplifier

A tuned amplifier is an electronic amplifier which includes bandpass filtering components within the amplifier circuitry. They are widely used in all kinds of wireless applications.

A typical multi-stage tuned amplifier

There are several tuning schemes in use,

• Staggered tuning where each amplifier stage is tuned to a slightly different frequency.
• Synchronous tuning (explained in more detail in the staggered tuning article) where each amplifier stage is tuned identically. This scheme maximises the amplifier gain but has narrower bandwidth than staggered tuning.
• Double-tuned amplifier. This scheme is used on amplifier stages that are transformer-coupled rather than capacitor coupled. Both the primary and secondary coils of the transformer are tuned. This has the effect of widening the bandwidth. Other tuning schemes are sometimes called single-tuned to distinguish them.