Frequency Modulator Transmitterusing Bipolar Junction Transistor?

Question

i need a breif description with block diagram, circuit diagram

FM transmitter using BJT

this is for an assignment
not a project to be demonstrated

Answer 1

Try Radio Shack. If there is not an RS store near you, try a Hartley or Colpitts oscillator, using BJT's. (You probably can't do this with just a single semiconductor device, the function is more complicated than that.) Then use something like a varactor diode (also known as a varicap diode) to do the tuning. Use a good quality crystal or ceramic microphone, and the voltage it produces will alter the capacitance of the diode, which will, in turn, change the frequency of the transmitter slightly, which is what you want. If you calculate carefully and chose your components correctlly, you can broadcast in the middle of the FM band (in America, 88 -- 108 MHz.) You can listen to it with your own FM radio, then. To avoid violating the FCC laws, make sure your signal is less than 100 milliwatts (1/10 watt) and your antenna is less than 10 feet long. Have fun!

5 NOV 06, 1515 hrs, GMT.

Answer 2

in the journey that your searching for residences of a particular BJT, generally you will discover them on the datasheet. Goto Google or Yahoo, and in basic terms sort interior the area selection. generally, it relatively is #a million or 2 on the checklist.