RADIO COLLAR TRANSMITTER

1. This is the circuit diagram of a radio transmitter suitable for fitting on radio collars.
2. The circuit transmits a pulse in the FM between band 88MHz to 105Mhz , which can be adjusted.
3. IC Ne 555 is wired as an astable multivibrator for producing the tone.L1 ,C3 and Q1 forms the modulator.
4. Q2 performs the final power amplification. 
5. For the inductor make 5 turns of .5 mm dia insulated copper wire on a standard ball pen refill.
6. Remove the refill and make a tap at the center of coil.
7. 
   
   To vary transmission frequency experiment with number of turns.
8. 
   
    Carefull! what ever may be the no of turns the tap must be at center.Use a 50 Cm long insulated copper wire as antenna.
   

   
   

   
   

   
   

   
   

   PART LIST:
   

   • R1…………………………………. 10K

   • R2 …………………………………1 M Ohm

   • R3 ………………………………….330 Ohm

   • R4 …………………………………..1 M Ohm

   • R5……………………………………. 330 Ohm

   • R6 ……………………………………200 Ohm POT

   • C1 ……………………………………..0.1 uF Ceramic

   • C2…………………………………….. 0.01 uF Ceramic

   • C3…………………………………….. 13 pF Ceramic

   • C4 ,C5, C6,C5 ……………………..0.01 uF Ceramic

   • Q1 ,Q2 ………………………………..2N4392 JFET

   • D1 ……………………………………….1N 914 Diode

   • IC 1……………………………………… NE 555