Fm transmitter works at a frequency of 88-108 MHz and has a range of about 300 meters kebih, voltages used around 9 volt s / d 12 volt DC.
In order to further transmission power can use directional antennas yagi type.
The workings of the transmitter can be explained as follows:
Microphon convert sound vibrations into electrical vibrations and will be forwarded (clutch) by c4 to Q2 to be amplified and then transmitted (clutch) by c3 to Q1 for blending (modulation) with a high frequency generated by the C5 and Lc to produce radio waves emitted by the antenna.
Gambar Skema Rangkaian PemancarKeterangan gambar
C1 = 0.001uf
C2 = 5.6pf
C3, C4 = 10uf / 16V (ELCO)
C5 = 3-18pf
R1 = 270 Ohm 1/4W
R2, R5, R6 = 4.7k 1/4W
R3 = 10K 1/4W
R4 = 100K 1/4W
Q1, Q2 = 2N2222A (NPN transistors) atau 2N3904
L1, L2 = 5 lilit
MIC = Electret Microphone
Sumber tegangan 9 Volt DC 2.
Pemancar mini fm ronica sc 197 Pemancar ini daya pancarnya bisa diatas 1km dengan ketinggian antena 5m.