Fm Transmitter

FM Transmitter Here is the schematic, PC board pattern, and parts placement for a low powered FM transmitter. The set forth of the transmitter when running at 9V is more or less 300 feet. Running it from 12V increases the range to active 400 feet. This transmitter should not be used as a fashion or telephone bug. PartTotal Qty. DescriptionSubstitutions C110. 001uf Disc capacitor C215. 6pf Disc capacitor C3,C4210uf Electrolytic Capacitor C513-18pf Adjustable Cap R11270 Ohm 1/8W Resistor270 Ohm 1/4W ResistorR2,R5,R634. 7k 1/8W Resistor4. 7K 1/4W Resistor R3110k 1/8W Resistor10K 1/4W Resistor R41100k 1/8W Resistor100K 1/4W Resistor Q1, Q222N2222A NPN Transistor2N3904, NTE123A L1, L225 Turn Air consequence Coil MIC1Electret Microphone MISC19V Battery Snap, PC Board, Wire For Antenna L1 and L2 are 5 turns of 28 AWG enamel coated attraction wire wound with a within diameter of about 4mm. The inside of a ballpoint pen works salubrious (the plastic tube that holds the ink).Remove the form later on winding then install the scroll on the circuit board, being studious not to bend it. C5 is used for tuning. This transmitter operates on the normal broadcast frequencies (88-108MHz). Q1 and Q2 kindle also be 2N3904 or something similar. You jakes use 1/4 W resistors mounted vertically instead of 1/8 W resistors. You may loss to bypass the battery with a . 01uf capacitor. An forward pass may not be compulsory for operation.