The I.F. Amplifier

if amplifier
Because this is an intermediate frequency between the original RF frequency and the audio we are trying to recover, 10.7MHz is called the Intermediate Frequency and its filter/amplifier is called the I.F. Amp.

(Some receivers may use other I.F. frequencies but, for simplicity, we'll stick with our 10.7MHz which is a very common standard)

Because we are now dealing with a single, fixed frequency, note the lack of variable capacitors in this picture. The blue, yellow, black and orange coloured slots are the tops of iron-dust cores which can be screwed into or out of their coils. These are used by a service engineer to 'fine tune' the amplifier to be at its peak at 10.7 MHz - and are the ones do-it-yourselfers usually fiddle with and make things worse!

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