I have this really nifty no coil - no trimmer fm mic that i built from the somewhere on the web. It works great but, the circuit can only transmitt on a fixed frq. The transmitter works on 3 main components and a few others. They are IC-CD4069, BB109 varicap diode and a 10.7mhz ceramic xtal. PLEASE HELP. Can i maybe bias the diode. Many thanks. If u wish to view it the address is https://www.electronic-circuits-diagrams.com/radioimages/radiockt8.shtml
I would think you can very the freq. by loading the xtal with a parallel capacitor. A series coil would also bend the freq., no?
Adding a tuned circuit at the antenna would clean up the output some.
Edit: It's not a crystal actually but a filter but it might still be bendable. You might try to replace the filter with a crystal.
Or at least add another transistor stage with a tank circuit tuned to 96.3 Mhz. That way you'd get more range with very little frequency drift and it wouldn't be spraying all over the spectrum.