Dear Mr. Nitin Vikas Deshpande,

A suitable prescaler integrated circuit is the SAB6456. It can measure up to 1300 MHz (VHF-UHF). It is a divide by 256 and is used in commercial frequency counters.

You can get the datasheet at the following web address.

wwww.ges.cz/sheet/sa-sm/sab6456.pdf

Another site with has schmatic can be found at the following web address.

http://mujweb.atlas.cz/www/pira/counter.htm

Thank you,

Charles Bannister