help needed to design a fm reciver

[vencatesh]

i m using a pll ic 565 to design my receiver but it limits the frequency to a max of 500khz so cud some one help me to design it for abt 100mhz as my transmitter is transmitting at 95.6mhz..

 

[audioguru]

The LM565 was stopped being made about 11 years ago. It is very old.
Modern FM radios might use a PLL IC that you cannot buy unless you order thousands of them.

Most FM radios use a super-heterodyne circuit.
Buy an FM radio and use its parts to make your own circuit.

 

[TheVictim]

Consumer electronics are so dirt cheap and precisely engineered these days that you should "cheat" whenever you can and hack them into your projects.
You'll save time and money, and get much better results than you can building things yourself.

 

[vencatesh]

no i need help on how do i step down high frequency into the working range of the pll 565 ie from say 96.5mhz to say 200khz..

 

[Nigel Goodwin]

200KHz is much too low, it doesn't give enough bandwidth for broadcast FM signals (IF used is 10.7MHz). FM radios are very old tried and tested technology, perhaps you should study how they work before trying to design one?.

 

[Leftyretro]

no i need help on how do i step down high frequency into the working range of the pll 565 ie from say 96.5mhz to say 200khz..

Usually the final LO frequency (96.5mhz) is sent through divider logic stages so that it comes out of the dividers at the same frequency as the PLL reference frequency (200khz), then onto the phase comparator. The dividers are usually programmable so that the final LO frequency can to changed in steps equal to the reference frequency, that is 200khz steps.

That make sense?

Lefty