Difference Between Frequency Locked Loops (FLL) and Phase Locked Loops (PLL) for Autotuning

Hey everyone

I've been scouring the internet looking for any information on frequency locked loops but it's been dismal at best. I'm not actually sure if a phased locked loop will do the same thing, but essentially I'm looking for something to automatically tune to a given frequency.

Is there a real difference between FLLs and PLLs? If so, where can I find information on this?

Additionally, I am trying to avoid use of modern chips like 4046s, instead preferring transistors, or even better, if possible, passive components only. I don't know if this is possible.

Could anyone help me shed some light on this?

I'm mostly interested regarding autotuning to a signal within a given bandwidth, such that the circuit would automatically retune itself to the strongest frequency.

A phase-locked loop is what you want. These have been described as actually being frequency-locked loops.

Amazon.com stocks many good books on PLLs. You might want to use the 4046 IC to get some experience and then switch to a discrete circuit design.

Take a look at the LM 565 chip