Off Topic

KJ.Kate proclaimed:

You beat a locally generated frequency against the incoming radio frequency signal. The radio is tuned by varying that local frequency. The result of the beat is a intermediate frequency that is always exactly the same, making it much easier to design a narrow band RF amplifier to amplify the signal up to where it is then converted into an audio signal.

At one point, it was hot stuff.

KJ.Kate proclaimed:

Originated in 1918, also known as an Armstrong design after the guy who first got credit for the idea. Which means of only Bill Hughes would remember the guy...

It still is. Nearly all radios made today use the superheterodyne principle. Many change the frequency more than once. Hence, dual-IF, triple-IF, etc. Crystal sets didn't, but you can bet the radio in your car does.

Dick

You probably still have a superhetrodyne setup if you own an AM radio

- it's a way of selecting and filtering the signal you want to avoid interference from adjacent channels.

More cars had radios than some here seem to th> So, exactly what IS a Superheterodyne ?????

ouch !! Sadly, its true ! Guess I look older than 38 then.